Kortex: Revenue, sale and how it was built
Kortex (Chrome extension that adds import, folders, export and automation to Google's Gemini Notebook (formerly NotebookLM), India): US$231K payment-verified revenue in 2026 and sold for an undisclosed price, October 2026. Evidence grade A: disclosed by a company or a filing, or verified by a payment processor. Team: 2 founders listed on TrustMRR; AppSumo lists 1 to 10 people; exact headcount not published. Launched August 2025; sold 14 months after launch.Added 27 October 2026
- Outcome
- US$231K payment-verified revenue in 2026 and sold for an undisclosed price, October 2026
- Evidence
- A disclosed by a company or a filing, or verified by a payment processor
- Launch
- August 2025
- Status
- Sold, 14 months after launch
- Team
- 2 founders listed on TrustMRR; AppSumo lists 1 to 10 people; exact headcount not published
- Outside funding
- None; TrustMRR and AppSumo both say Bootstrapped
- Main channel
- Inside another platform
Kortex is a browser extension, a small program that runs inside Chrome and changes the pages the user visits. It works on Google's Gemini Notebook, the research tool that answers questions from the sources a user uploads, and that Google called NotebookLM until 16 July 2026. Kortex adds import buttons to the AI chat apps, a workspace with collections and tags, export to files, automation rules, a podcast feed for the generated Audio Overviews, and an MCP server, a connector that follows the Model Context Protocol so that an AI assistant such as Claude or ChatGPT can read and fill the user's notebooks. The company is a two-founder project from Surat, India, led by Yaksh Gandhi; the TrustMRR profile lists a co-founder by the first name Jill.
The money is read by TrustMRR from the company's Dodo Payments account through an API key, a password that lets one program read another program's records: US$231,297 from January to 26 October 2026, which is also the all-time total on that account, and US$3,343 of MRR, monthly recurring revenue, the sum of the active subscriptions counted per month, from 1,027 subscriptions. February and March 2026 brought US$109,610, 47.4% of the total (calculated), when the site sold a US$49 lifetime licence at half price; September 2026 brought US$4,049, 92.8% less than March. Sales through AppSumo, where the same deal is still listed, are paid by AppSumo and are not in these figures.
Between 20 September and 13 October 2026 the home page gained the line 'Acquired by FschoolAI', a student study platform. No price, date or buyer statement is published, and the TrustMRR profile still shows the business listed for sale at US$50,000 since 30 January 2026. This page grades every number: the Dodo Payments figures are grade A, the Chrome Web Store, Product Hunt and Internet Archive records are grade B, and everything the founders wrote, including the acquisition line, is grade C.
How much did Kortex make, and what was it sold for?
Each row shows the evidence grade and the source numbers from the list at the end of this page. The grades are explained in How Aiolum verifies.
| Fact | Value | Grade | How we know | Sources |
|---|---|---|---|---|
| Total revenue, January to 26 October 2026 | US$231,297 | A | Read by TrustMRR from the company's Dodo Payments account through an API key, last synced on 26 October 2026 at 15:07 UTC. The last-12-months and all-time figures are the same, because the verified history starts in January 2026 (US$20,146 that month). | [1] |
| MRR, 26 October 2026 | US$3,343 from 1,027 active subscriptions | A | Monthly recurring revenue counts monthly plans at their price and yearly plans at one twelfth of the yearly price. Lifetime licences are not in it. TrustMRR shows MRR down 2.2% in the last 30 days. | [1] |
| Revenue in the last 30 days, to 26 October 2026 | US$2,250 | A | Same source. The stored snapshot shows US$2,309 and a fall of 51.6% from the 30 days before. Last 3 months US$19,202, last 6 months US$74,290. | [1] |
| Verified revenue per month, 2026 | US$20,146 in January, US$53,034 in February, US$56,576 in March, US$27,813 in April, US$14,520 in May, US$25,384 in June, US$15,961 in July, US$11,977 in August, US$4,049 in September, US$1,838 in October to the 26th | A | TrustMRR monthly timeline. February and March together are US$109,610, 47.4% of the total; September is 92.8% below March; the average of the last three months, US$5,955, is 13.8% of the first-quarter average of US$43,252 (all calculated). | [1] |
| MRR times 12 | US$40,116 a year | calc | Calculated: US$3,343 times 12. This counts only the subscriptions, not the lifetime licences that made most of the 2026 revenue. | [1] |
| Average MRR per active subscription | US$3.26 a month | calc | Calculated: US$3,343 divided by 1,027. Below today's yearly Pro price of US$4.92 a month, and close to the earlier yearly prices of US$29 (US$2.42 a month) and US$45 (US$3.75 a month) that many subscribers still pay. | [1, 13, 14] |
| Why revenue is far above MRR | one-time lifetime licences, US$49 in January 2026 and US$199 to US$200 since September | C | The pricing pages in the Internet Archive and today. A lifetime licence counts once in revenue and never in MRR. TrustMRR does not publish how many were sold. | [13, 14, 2] |
| Visitors and revenue per visitor, last 30 days | 4,647 visitors; US$0.51 per visitor | A | TrustMRR reads traffic through the Google Analytics API, which the profile marks as connected. US$2,250 divided by 4,647 is US$0.48 (calculated); the profile's US$0.51 uses its own window. | [1] |
| Acquisition | 'Acquired by FschoolAI', price not disclosed, between 20 September and 13 October 2026 | C | The company's home page carries the line with a link to fschoolai.com, which describes itself as a student academic intelligence platform. The Internet Archive copy of 20 September 2026 does not have the line; the copy of 13 October 2026 does. No press, buyer statement or price was found. The TrustMRR profile still says 'Listed for sale'. | [2, 14, 15, 1] |
| Listed for sale on TrustMRR | asking US$50,000, first listed 30 January 2026 | C | Listing tier Free, revenue multiple 1.8x, 9 acquisition offers received, 8,636 interested buyers who saw it recently. The asking price is 1.25 times MRR times 12 and 0.22 times the 2026 revenue (calculated). | [1] |
| Chrome Web Store listing | 100,000 users, 4.4 stars from 394 ratings, Featured, version 2.3.6 of 8 October 2026 | B | A record kept by Google, read on 27 October 2026. The store says the publisher 'has a good record with no history of violations' and that the extension 'Follows recommended practices for Chrome extensions'. Size 4.63 MiB, 8 languages, offers in-app purchases. | [10] |
| User counts on the company's own pages | 'Loved by 28k+ Users' on 30 January 2026, '130k+' on 20 September 2026, '100,000+' on 27 October 2026 | C | Internet Archive copies and the live page. The TrustMRR profile estimates 130,000 users. The export and import counters, '200k+ exports' and '105k+ imports', are the same in January and in October 2026. | [13, 14, 2, 1] |
| Product Hunt launches | 9 December 2025: number 5 of the day, 190 votes, 20 comments; 14 January 2026: number 179, 1 vote | B | Product Hunt product page and launch pages, read on 27 October 2026. The maker is listed as Yaksh Gandhi. | [11] |
| AppSumo deal | lifetime licences at US$49, US$79 and US$159, 51% off a list price of US$99; 25 reviews, 3.6 of 5 | B | AppSumo listing, read on 27 October 2026. The company fields, filled in by the maker, say founded 7 August 2025, Surat, Gujarat, India, 1 to 10 people, Bootstrapped. The founder's message: 'Over 100K power users found us without a single ad'. | [12] |
| Affiliate program | 10% of every payment for as long as the customer stays; 'US$4,000+ paid to affiliates so far' | C | Company's affiliate page. At 10%, US$4,000 of commissions means about US$40,000 of referred payments (calculated). Minimum payout US$100, paid monthly in US dollars. | [6] |
| Creator pass | 3 months of Pro free for teachers and creators; their students pay US$41.30 for the first year instead of US$59 | C | Company's creator page. Teachers with a school email address are approved at once. | [7] |
| Profit margin, last 30 days | 98.0% | C | TrustMRR snapshot, outside its list of payment-verified metrics. | [1] |
| Team | founder Yaksh Gandhi and a co-founder listed as Jill; 1 to 10 people on AppSumo | C | TrustMRR profile fields and the AppSumo company card. The About page calls Kortex 'a small independent project'. The blog's rename article is signed Juli. No page gives a headcount. | [1, 12, 3, 9] |
| Outside funding | none | C | TrustMRR: Funding not listed; AppSumo: Bootstrapped. The About page: 'not a venture-backed roadmap'. | [12, 3] |
| Country | India (Surat, Gujarat); the privacy policy says the service is 'principally operated from the United States' | C | TrustMRR gives the country as IN; AppSumo gives the city. The privacy policy, effective 30 September 2026, names United States infrastructure. | [1, 12, 5] |
| Technology | JavaScript extension; Firebase Authentication and Firestore; Cloudflare R2 for audio; Dodo Payments; an inference gateway or an outside AI processor for AI requests; 'reverse-engineered APIs' of Gemini Notebook | C | TrustMRR tech stack fields and the privacy policy. The marketing site is built with Astro (visible in the page source, grade B). No source names the AI model used for Kortex's own generation features. | [1, 5, 2] |
| Gemini Notebook rename | NotebookLM became Gemini Notebook on 16 July 2026 | C | Kortex's own blog post, which cites Google's announcement and gives more than 30 million users for the product at that time. Kortex's domain and store listing keep both names. | [9] |
| Time from the founding to the October 2026 figures | 14 months | calc | Calculated: August 2025 to October 2026. From the Product Hunt launch in December 2025 it is 10 months. | [12, 11, 1] |
How to read this table: a grade A value was read by TrustMRR from the company's Dodo Payments account or Google Analytics through an API key; it is not a founder statement. A grade B value is a record kept by an outside platform: the Chrome Web Store, Product Hunt, AppSumo or the Internet Archive. A grade C value is a statement by the founders or the company, a profile field that a founder filled in, or a reviewer's description. A "calc" value was computed on this page from the rows above it.
| Plan | Per month, billed yearly (US$) | Per month, billed monthly (US$) | Limit |
|---|---|---|---|
| Free | 0 | 0 | 10 imports a day from 15 sites, 10 exports a day, 10 saved prompts, this browser only |
| Pro | 4.92 | 9.99 | no daily limits, sync, bulk import, automations, templates, 1,000 podcast minutes, Kortex MCP |
| Lifetime | 200 one-time | everything in Pro, 2,000 podcast minutes, unlimited MCP with fair use | |
| Teams | 12 | per seat, billed yearly, minimum 3 seats; shared prompts and notebooks | |
| AppSumo lifetime deal, tier 1 | 49 one-time | tier 2 US$79, tier 3 US$159; sold by AppSumo, outside the verified figures |
The home page shows Pro at US$4.92 a month when billed yearly, US$59 a year, and its price data gives Pro monthly at US$9.99; the page calls the yearly plan '6 months free' and says 'You save $60.88 a year' (calculated: 12 times US$9.99 minus US$59). Lifetime is one payment of US$200. Teams is US$12 per seat a month, billed yearly, minimum 3 seats. All plans have a 7-day money-back guarantee and checkout runs on Dodo Payments. The prices rose through 2026: the Internet Archive shows Pro at US$2.4 a month (US$29 a year) and Lifetime at US$49, marked 50% off US$100, on 30 January 2026, and Pro at US$3.75 a month (US$45 a year) and Lifetime at US$199 on 20 September 2026. Yearly Pro therefore doubled in nine months (103.4%, calculated) and Lifetime rose about four times. AppSumo still sells lifetime licences at US$49, US$79 and US$159, marked 51% off; those payments go through AppSumo and are not in the verified figures.
When did Kortex launch, and how did it grow?
From a free extension founded in August 2025 to US$231,297 of verified revenue and a sale for an undisclosed price in about 14 months, with 47.4% of the money made in two months. Each entry carries its grade.
- 7 August 2025CFounding date on the AppSumo company card, Surat, Gujarat, India. [12]
- 9 December 2025BLaunch on Product Hunt as 'Organize, import + export NotebookLM sources with a click': number 5 of the day, 190 votes. [11]
- 12 December 2025CChatGate describes the extension as built by Yaksh Gandhi and 'currently appears to be free and not monetized'. [16]
- 14 January 2026BSecond Product Hunt launch, 'Capture. Automate. Listen.': number 179 of the day, 1 vote. [11]
- January 2026AFirst month of verified revenue on Dodo Payments: US$20,146. [1]
- 30 January 2026BInternet Archive copy of the home page: 'Loved by 28k+ Users', Pro at US$2.4 a month billed US$29 a year, Lifetime Pro at US$49 marked 50% off, an Enterprise plan with single sign-on. The same day the business is listed for sale on TrustMRR at US$50,000. [13, 1]
- February and March 2026AVerified revenue of US$53,034 and US$56,576, the two best months, 47.4% of everything the account has taken. [1]
- 16 July 2026CGoogle renames NotebookLM to Gemini Notebook, according to Kortex's blog. Kortex keeps both names in its domain and store listing. [9]
- 26 July 2026COn AppSumo the founder apologises for a 'Failed to load notebooks' error caused by network blocks on requests to notebooklm.google.com and submits a fix to the Chrome Web Store. [12]
- September 2026CKortex MCP enters private beta, so Claude, ChatGPT, Cursor and Codex can read, search and add to notebooks. Verified revenue falls to US$4,049 (grade A). [4, 1]
- 20 September 2026BInternet Archive copy: 'Loved by 130k+ Users', Pro at US$3.75 a month billed US$45 a year, Lifetime at US$199, Teams from US$432 a year. No acquisition line. [14]
- 30 September 2026CNew privacy policy takes effect: sign-in by Firebase, audio in Cloudflare R2, page material may be used to train models, 'reverse-engineered APIs'. [5]
- 8 October 2026BVersion 2.3.6 in the Chrome Web Store; the October changelog says MCP is out of beta and the extension opens in a side panel. [10, 4]
- 13 October 2026BInternet Archive copy of the home page now shows 'Acquired by FschoolAI'. No price or date is given. [15]
- 26 October 2026ATrustMRR reads US$231,297 of 2026 revenue, US$3,343 of MRR from 1,027 subscriptions and a 51.6% fall in 30-day revenue. The home page sells Pro at US$59 a year or US$9.99 a month and Lifetime at US$200, and still carries the acquisition line. [1, 2]
Why did Kortex work?
Four causes, in the order they mattered. Each one is a reusable lesson.
Sell the missing half of a free Google product
Gemini Notebook is free and had more than 30 million users at the rename in July 2026, but it had no folders, no export and no public API for personal accounts, according to Kortex's own blog. Kortex charged for exactly those gaps. The About page puts it as: 'brilliant at helping you think, and bad at letting you keep what you thought'. The customer already uses the AI; Kortex pays no model cost for the core features.
The store is the channel
The extension is installed from the Chrome Web Store, where Google marked it Featured and where it shows 100,000 users and 394 ratings. The founder wrote on AppSumo that more than 100,000 users came 'without a single ad'. Two Product Hunt launches, an AppSumo deal, a 61-post blog about Gemini Notebook, a 10% affiliate program and free Pro for teachers add to it.
Lifetime deals front-load the money
A US$49 lifetime licence at half price in January 2026 brought the two best months, US$109,610 in February and March, 47.4% of all verified revenue. The cost is visible later: subscriptions bring US$3,343 a month, and the 30-day revenue of US$2,250 is 51.6% below the month before. The Lifetime price was raised to US$199 to US$200 by September.
Ride the platform's new features
When Google added Audio Overviews, Kortex added a podcast feed for them; when assistants gained MCP, Kortex shipped an MCP server with '145+ notebook tools'; when Google renamed the product, Kortex rewrote its pages with 'formerly NotebookLM' and a blog post about the rename. Each Google change is a reason to update, and a risk, because the extension depends on 'reverse-engineered APIs' that Google can change.
How it was built
These details come from the TrustMRR profile fields, the company's privacy policy and pages, and the source code of its marketing site. They are grade C unless marked. [1, 5, 3, 2, 4]
- A Chrome extension in JavaScript that works in Chrome, Edge, Brave and other Chromium browsers, with a side panel, a dashboard and buttons injected into Gemini Notebook and into the chat apps (ChatGPT, Claude, Gemini, Perplexity, Grok, Kimi and others).
- Sign-in by Firebase Authentication through Google OAuth; prompts, folders, tags, notes, templates and automation rules stored in Google Cloud Firestore; generated podcast audio in Cloudflare R2.
- Chat transfers 'are processed in memory and go straight from your browser to your own Gemini Notebook account'; the privacy policy says Kortex does not keep the conversations or the notebook documents.
- Access to Gemini Notebook goes through 'third-party and reverse-engineered APIs', in the words of the privacy policy's definition of Lifetime; Google has no public API for personal accounts, according to Kortex's blog.
- AI requests 'can pass through our inference gateway or an outside AI processor' with no-retention terms; the provider and model are not named.
- Payments by Dodo Payments, the account that TrustMRR reads (grade A), with AppSumo licence keys for the deal buyers.
- The marketing site is built with Astro and serves a Markdown copy of each page for AI agents (visible in the page source, grade B).
- Kortex MCP: an MCP server with more than 145 tools, used from Claude, ChatGPT, Cursor, VS Code or Codex, out of beta in October 2026; also a Claude Code plugin.
Tools named in the sources
Each one opens its page in the Tools tab, with every story that uses it.
Who tried this before Kortex, and why did they fail?
Five companies in the Loot Drop database built a better layer on top of a platform they did not own, and the platform owner or a free built-in feature replaced them. The values below are from that database and are not independently verified.
Xobni
The promiseA smarter inbox inside Microsoft Outlook.
Why it diedTied to Outlook, which Microsoft improved itself; mobile made the desktop add-on irrelevant. Yahoo bought the remains.
Xmarks
The promiseSync bookmarks and tabs across browsers.
Why it diedChrome, Firefox and Safari built sync in, free.
Kippt
The promiseA pretty bookmarking tool against information overload.
Why it diedPocket and Evernote offered the same with more integrations; the social features did not spread.
Niles
The promiseA company knowledge base as a bot inside Slack.
Why it diedSlack added similar AI features itself, and Guru and Confluence grew faster.
Delicious
The promiseTag and share web links from anywhere.
Why it diedYahoo bought it in 2005 and let it stagnate while browsers and phones changed how people saved links.
The failed startups come from Loot Drop, a free database of dead startups, retold here in our own words. Loot Drop describes its entries as AI-assisted summaries of public sources, so these cards carry no evidence grade.
What changed
Each predecessor added organisation or sync to a platform it did not control, and the platform owner closed the gap by building the feature or by changing the interface. Kortex sits in the same position, and more exposed: its features reach Gemini Notebook through endpoints that Google did not publish, which the company itself calls reverse-engineered. In July 2026 Google added its own collections, and Kortex's changelog records a one-click move of Kortex collections into them.
What differs is the cost side and the speed. Kortex spends nothing on content or on the AI model: the user already has the notebook, and the extension moves data in and out. It charged from the first month of 2026, took most of its money through one-time licences before the platform could react, and was sold within nine months of its first verified revenue. The founders did not try to outlast Google; they took the money in a window and left.
Can one person copy Kortex now?
The structure, yes, with a short clock.
A two-founder team in India took US$231,297 in ten months by selling folders, export and automation for a free Google product with tens of millions of users, through Google's own store and two deal launches, with no outside money. The method works for any large AI product that ships without organisation or export. The clock is set by the platform: once Google adds the feature or changes the endpoints, the extension's value falls, and Kortex's 30-day revenue was already down 51.6% when it was sold.
Where it is still open: Any AI assistant or notebook without export, folders or an API for personal accounts; the same gap exists around chat apps, image tools and the new agent products, and it closes each time the vendor ships the feature.
- 1Pick a free AI product with millions of users and list what its users do by hand: getting data in, finding it, getting it out.
- 2Build the missing half as a browser extension and list it in the store, where the users already are; apply for the Featured badge.
- 3Charge from the start, and use a cheap lifetime licence and a deal site to turn early users into cash before the platform reacts.
- 4Watch the platform's roadmap; move each feature it adopts into a bridge to the native version, and keep the price rising while the window is open.
What could go wrong for Kortex?
The risks are the mirror image of the causes above.
Sold for an undisclosed price, while still listed for sale
The home page says 'Acquired by FschoolAI' with a link to fschoolai.com, a student study platform whose pages load by script and name no owner. The line appeared between the Internet Archive copies of 20 September and 13 October 2026. No press, no buyer statement and no price were found, and the TrustMRR profile, synced on 26 October 2026, still says 'Listed for sale' at US$50,000 with 9 offers. This page records an exit with no price because the company's own site says so; a reader should look for a statement from FschoolAI or a change on TrustMRR.
Half the revenue came in two months
US$109,610 of the US$231,297, 47.4%, arrived in February and March 2026, when the site sold a US$49 lifetime licence marked 50% off. Verified revenue fell to US$4,049 in September and US$1,838 in October to the 26th, 92.8% and more below March. The part that repeats is US$3,343 of MRR from 1,027 subscriptions, US$3.26 each on average. The 30-day revenue of US$2,250 is above this site's floor of US$2,000 a month, but the trend is down.
The decision rule applied: unofficial access to a Google product
The 26 October 2026 rule stops a product that is 'an unofficial API or wrapper that resells a provider's service against that provider's terms'. Kortex's privacy policy says 'Lifetime' lasts 'as long as required third-party and reverse-engineered APIs continue to function', and its MCP server gives AI assistants '145+ notebook tools' for Gemini Notebook, which has no public API for personal accounts. Google's Terms of Service, effective 30 July 2026, forbid 'reverse engineering our services or underlying technology, such as our machine learning models, to extract trade secrets or other proprietary information, except as allowed by applicable law' and 'using automated means to access content from any of our services in violation of the machine-readable instructions on our web pages'. This page did not stop the story, because Kortex does not resell Google's service: every user signs in to their own Google account, and Kortex sells its own features around it. Google's Chrome Web Store marks the extension Featured and says the publisher has 'no history of violations'. The reading is the orchestrator's, open to the user's change.
Google's trademark in the domain
The domain kortex-notebooklm.com and the store title 'Kortex NotebookLM: Gemini Notebook Toolkit' use Google's product names. The footer says 'Gemini Notebook and NotebookLM are trademarks of Google LLC. Kortex is an independent extension', and the store listing says the extension 'is not affiliated with or endorsed by Google'. A trademark complaint would hit the domain and the listing at once.
The decision rule applied: purpose gate on the home and pricing pages
Read on 27 October 2026, the home page sells import, organisation, automation, export, a podcast feed and the MCP server; the pricing section sells daily limits, sync, bulk import, automations, templates, podcast minutes and MCP access. Neither page contains 'undetectable', 'humanizer', 'bypass', 'Parasite SEO', income promises or fake-account posting. The affiliate page states its commission, '10% of every payment from each customer you refer', which the 26 October 2026 rule allows; no page claims how much users earn. The testimonials on the home page and the Customer love page link to named Chrome Web Store reviews and one Product Hunt comment, so they are not fabricated. The banner 'Infiltrating the world's best institutions', with a list from OpenAI to Spotify, is an unverified claim about where users work. The Chrome Web Store shows a related extension from another maker that advertises an 'AI Watermark Remover'; Kortex's own pages do not sell or link to such a tool.
A privacy policy that allows wide collection
The policy effective 30 September 2026 says that while Kortex is active on a tab, 'interface and interaction information, including material visible on the page, may be collected', that this 'can include names, email addresses, financial-account information, health information', that it is kept 'in the form received' in the United States for two years, and that it 'may be used to build, train, test, evaluate, or improve Kortex models and models operated by AI processors for us' and 'may be provided to third parties'. Users can turn this off in the settings, and the policy says the program 'may not yet be operating'. The same policy says Kortex 'is not designed for anyone younger than 18', while the blog markets the product to students.
What the sources do not say
No source gives the headcount beyond 'a small independent project' and AppSumo's '1 to 10'. The co-founder appears only as 'Jill' on TrustMRR, and the blog is signed 'Juli'. The AI model behind Kortex's own generation features, the number of lifetime licences sold, the AppSumo revenue and the terms of the acquisition are not published. The 98.0% profit margin is a founder-entered field. The founder's X account and Reddit posts were not read, because this site does not fetch those services.
Sources
The grade next to each source is the best grade that the source can support. "Read in full" means that the text of the page was downloaded and the numbers were checked in it.
- A TrustMRR: Kortex-Notebooklm, payment-verified revenue profile, synced 26 October 2026Read the markdown profile (https://trustmrr.com/startup/kortex-notebooklm.md) in full on 27 October 2026, live copy synced on 26 October 2026 at 15:07 UTC. The revenue, MRR, subscription and monthly figures were read from Dodo Payments through an API key, and the visitor figures through the Google Analytics API. The description, founders, country, user estimate, pricing, tech stack, profit margin and sale listing fields are not in the verified list and are grade C.
- C Kortex home page: Research Workspace for Gemini Notebook & NotebookLMRead in full on 27 October 2026, the HTML page and the Markdown copy the site serves at /index.md. Source for the features, the prices and their structured price data, the user and ratings counts, the testimonials with their links, the institutions banner, the MCP server and the 'Acquired by FschoolAI' line.
- C Kortex: About, made by people who live in Gemini NotebookRead in full. Source for the reason for the product, the data commitments, 'a small independent project' and the trademark footer.
- C Kortex changelog: What's new in KortexRead in full. Source for the releases from May to October 2026, the MCP beta and the collections bridge.
- C Kortex privacy policy, effective 30 September 2026Read in full. Source for Firebase, Firestore, Cloudflare R2, Dodo Payments, the AppSumo licence keys, the AI processors, the training clause, the two-year retention, the 'reverse-engineered APIs' and the 18+ rule.
- C Kortex affiliates: Share Kortex, earn 10% every time they payRead in full. Source for the commission, the payout rules and the 'US$4,000+ paid to affiliates so far' figure.
- C Kortex creator pass: Teach with Kortex, get Pro freeRead in full. Source for the free months and the student price.
- C Kortex: Customer love, what people say about Kortex, word for wordRead in full. Ten reviews, nine from the Chrome Web Store and one from Product Hunt, each linked to the original.
- C Kortex blog, Juli, 27 September 2026 (updated 26 October 2026): NotebookLM Renamed: Is Gemini Notebook (formerly NotebookLM) the Same?Read in full. The company's account of Google's rename on 16 July 2026, the 30 million users and the missing public API, citing Google's own posts.
- B Chrome Web Store: Kortex NotebookLM: Gemini Notebook ToolkitRead the listing on 27 October 2026. A record kept by Google: users, ratings, the Featured badge, the publisher record, the version and update date, the size, the languages, the data disclosures and the related extensions.
- B Product Hunt: Kortex, organize, import + export NotebookLM sources with a click, with its two launchesRead the product page and the two launch pages (launches/kortex-4 of 9 December 2025 and launches/kortex-3 of 14 January 2026) on 27 October 2026, including their embedded data for the ranks and votes. The maker is listed as Yaksh Gandhi.
- B AppSumo: Kortex, lifetime deal, US$49 once, no subscriptionRead in full on 27 October 2026. The deal tiers, the review count and rating are AppSumo records (grade B); the company card, the founder's message and the seven founder updates from July to September 2026 are written by the maker (grade C).
- B Internet Archive copy of kortex-notebooklm.com, 30 January 2026Read in full. The earliest copy that the Wayback availability API returns: user count, 2026 prices, Enterprise plan, testimonials.
- B Internet Archive copy of the Kortex home page, 20 September 2026Read in full. Source for the September prices and user count, and for the absence of the acquisition line.
- B Internet Archive copy of the Kortex home page, 13 October 2026Read the page source. The first archived copy with 'Acquired by FschoolAI'.
- C ChatGate, 12 December 2025: Kortex: One-Click Archive to NotebookLMRead in full. A directory's description that names Yaksh Gandhi as the builder, lists the December 2025 features and says the extension then appeared free and not monetized.
- C Google Terms of Service, effective 30 July 2026Read the section 'Don't abuse our services' and the software licence terms. Source for the clauses on reverse engineering, automated access and selling parts of Google's services, quoted in 'watch'.
- C Loot Drop database export, 1,749 failed startupsLocal export. AI-written summaries, not independently verified. Source for the failed predecessors.