Underpriced AI: Revenue, team and how it was built
Underpriced AI (Phone and web app for resellers that identifies an item from a photo, prices it from sold listings and drafts the eBay listing, Not stated (US dollar prices and a US company form, Underpriced AI LLC)): US$5.2K in the last 30 days, October 2026. Evidence grade D: reported, not verified. Team: 2 co-founders: Frank Kratzer (founder and developer) and Wendy Kratzer (thrifting and sourcing), per the company's about page; no employees named. Launched December 2025; still running, revenue flat.Added 6 November 2026
- Outcome
- US$5.2K in the last 30 days, October 2026Revenue flat
- Evidence
- D reported, not verified
- Launch
- December 2025
- Status
- Still running
- Team
- 2 co-founders: Frank Kratzer (founder and developer) and Wendy Kratzer (thrifting and sourcing), per the company's about page; no employees named
- Outside funding
- None reported
- Main channel
- Search and AI answers
What is not verified
Every revenue figure on this page, including the US$5,211.76 in the last 30 days, comes from Shipped & Paid, which read a Stripe-verified Indie Hackers revenue page on 30 October 2026 and listed the monthly totals. This page could not open that page, because Indie Hackers blocks Claude agents, and the founder's April 2026 figure of US$589 MRR is also known only through Shipped & Paid. A reader could look for a TrustMRR profile or the founder's own posts with the same figures. The headline number is grade D: one claim or one estimate, with no second source. Aiolum shows it because the story is useful, and marks it so that it is not mistaken for a verified figure.
Underpriced AI is a pricing and listing tool for resellers, people who buy used items cheaply and sell them online for more. The user takes a photo; a vision model, an AI model that reads images, names the item (brand, maker, model, era); the app then pulls sold comps, recent sales of the same item that show what buyers paid, and gives a price range and a written listing that it can publish to eBay. The company's own pages say it uses Anthropic's Claude models for the identification.
Frank Kratzer, a software engineer, built it with Claude Code, and the about page names Wendy Kratzer as co-founder for sourcing. The site was live by 30 December 2025. Shipped & Paid, a site that collects revenue cases, read a Stripe-verified Indie Hackers revenue page on 30 October 2026 and reported US$5,211.76 in the last 30 days, and monthly totals that rose from US$98 in January 2026 to about US$5,900 a month from July to September 2026.
The revenue figures rest on one retelling: Shipped & Paid's reading of a Stripe-linked page that this pipeline is not allowed to open, so the headline is grade D. Prices, features, the model provider and the team come from the company's own pages, its App Store listing and the founder's Hacker News post.

How much revenue does Underpriced AI make?
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 |
|---|---|---|---|---|
| Revenue in the last 30 days, read 30 October 2026 | US$5,211.76 | D | Shipped & Paid read it from the Stripe-verified Indie Hackers revenue page and marks the case Verified. This page could not open the Indie Hackers page (its robots.txt blocks Claude agents), so the figure rests on that one retelling. | [1, 2] |
| Run rate from the last 30 days | about US$62,541 a year | calc | Calculated: US$5,211.76 times 12. | [1] |
| Monthly revenue, January to September 2026 | US$98, US$149, US$841.25, US$1,959.57, US$3,082.61, US$4,442.91, US$5,942.93, US$5,620.74, US$5,893.49 | D | As Shipped & Paid listed them from the same Stripe-verified page. July to September stayed within 6% of each other. | [2] |
| Total revenue, January to September 2026 | US$28,031 | D | Shipped & Paid's total. The sum of the nine months computed on this page is US$28,030.50. | [1, 2] |
| Recurring revenue, 3 April 2026 | US$589 MRR from 36 paying subscribers and 842 users | D | The founder's update of 3 April 2026 as Shipped & Paid retold it. Shipped & Paid notes it fits April's US$1,959.57 once one-time scan packs are counted. | [2] |
| Organic search sessions | 2 in January 2026, 1,303 in March 2026 | D | The founder's figures as Shipped & Paid retold them. Organic search is the largest channel. | [2] |
| Team | 2 co-founders | C | The about page lists Frank Kratzer, Founder and Developer, and Wendy Kratzer, Co-Founder and Thrifting and Sourcing Specialist. Shipped & Paid quotes the founder: the app was originally built for his wife. | [5, 1] |
| AI model | Claude Sonnet 4.6 in March 2026; the company's pages name Claude Opus 5.5 in November 2026 | C | The founder's Hacker News post of 14 March 2026 gives about US$0.05 per photo scan for the vision call plus about US$0.004 for a Perplexity Sonar search. | [7, 6] |
| Cost of a barcode scan, March 2026 | about US$0.004, 92% below a photo scan | C | The founder's Hacker News post: a free UPC database lookup replaces the vision model for items with a barcode. | [7] |
| Usage counter on the home page, 6 November 2026 | 5,900+ resellers have priced US$2.8M+ of items | C | The company's own counter. US$2.8 million is the value of the items priced, not the company's revenue. | [3] |
| App Store rating, 6 November 2026 | 4.6 from 29 ratings, age rating 4+ | C | Seller: Underpriced AI LLC. | [8] |
| First public copy of the site | 30 December 2025 | C | The earliest Internet Archive capture of underpricedai.com: 'Never Underprice Again', with free sign-up and eBay listing. | [9] |
| Lowest paid plan | US$5 a month, or US$48 a year | C | Pricing page, 6 November 2026. | [4] |
| Outside funding | none reported | C | No source names a funding round or an investor. | [1, 5] |
| Time from launch to the headline figure | 10 months | calc | Calculated: December 2025 to October 2026. | [9, 1] |
How to read this table: a grade D value comes from one retelling that this page could not check at its origin. A grade C value is the company's or the founder's own statement. A "calc" value was computed on this page from the rows above it.
| Plan | Per month, billed yearly (US$) | Per month, billed monthly (US$) | Limit |
|---|---|---|---|
| Starter | 4 | 5 | 30 scans a month |
| Pro | 12 | 15 | 100 scans a month, automatic price drops, overnight listing drafts |
| Pro Plus | 23.17 | 29 | 240 scans a month, tags, storage locations, bulk tools, analytics, Sale Finder |
| Business | 47.08 | 59 | 550 scans a month |
| Power | 99 | 1,000 scans a month | |
| Scale | 199 | 2,500 scans a month | |
| Scan packs | 3 to 70 one-time | 5 to 250 scans |
The first scan is free and needs no card. Yearly billing saves 20%. Scans past the plan cost 25 cents each. Scan packs are one-time purchases whose credits do not expire.
When did Underpriced AI launch, and how did it grow?
From a family reseller's nightly price research to about US$5,900 a month in nine months. Each entry carries its grade.
- 30 December 2025CThe first Internet Archive copy of underpricedai.com: photo, AI valuation, comparable sales and one-click eBay listing. [9]
- January 2026DUS$98 of revenue in the month, as Shipped & Paid read the Stripe-verified page. [2]
- 24 January 2026DThe founder's launch post on Indie Hackers. Replying to commenters, he writes that he built it with Claude Code by prompts, originally for his wife, as Shipped & Paid quotes him. [1]
- 14 March 2026CShow HN post: barcode scanning added, at about US$0.004 a scan against about US$0.054 for a photo scan. Stack: Next.js, Prisma, Neon PostgreSQL, Vercel, Capacitor for the iOS and Android apps. [7]
- 3 April 2026DThe founder reported US$589 MRR from 36 paying subscribers and 842 users, as Shipped & Paid retold it. April revenue was US$1,959.57 by the same retelling. [2]
- July to September 2026DUS$5,942.93, US$5,620.74 and US$5,893.49 a month, by Shipped & Paid's reading of the Stripe-verified page. [2]
- 30 October 2026DShipped & Paid reads US$5,211.76 in the last 30 days. [1]
- 6 November 2026CThe site prices items with Claude Opus 5.5, offers plans from US$5 a month and runs as an MCP server listed in the Claude and ChatGPT directories, by its own pages. [4, 6]
Why did Underpriced AI work?
Four causes, in the order they mattered. Each one is a reusable lesson.
Search articles for the exact questions
Shipped & Paid reports that organic search is the largest channel: the founder writes articles on what resellers search for, such as antique identifier apps, thrift store apps and alternatives to the WorthPoint price database. The site also publishes value guides for single items with the median of their recent sales, a page type that can match many long searches.
Sold prices, not a model's guess
The model only names the item. The price comes from recorded sales: a specialist eBay sold-price API first, a backup service, and the company's own archive of more than a million sales, by its own description. The pricing page sets this against general chatbots that give a number without naming a sales source.
Small price, many ways to pay
Plans start at US$5 a month and scan packs at US$3, so a weekend thrifter can pay. The founder found that scans cost far more than he expected and changed the pricing, as Shipped & Paid retold, and barcode scans skip the vision model to cut the cost per scan.
Built for a known user
The app began as a tool for a reseller in the founder's family, who also appears on the about page as co-founder for sourcing. That gave the developer a daily tester with the real problem.
How it was built
These details come from the founder's Hacker News post, the company's own pages and Shipped & Paid's summary. They are grade C, except the Shipped & Paid quotations, which are grade D. [7, 6, 3, 1]
- Built with Claude Code through prompts, the founder said in a reply that Shipped & Paid quotes.
- Next.js 16 with the App Router, TypeScript, Prisma with Neon PostgreSQL, hosted on Vercel, per the March 2026 Hacker News post.
- One codebase for web, iOS and Android through Capacitor; the camera opens through the phone's own file picker instead of a live video stream.
- Identification by Anthropic's Claude vision models (Sonnet 4.6 in March 2026, Opus 5.5 named in November 2026); Perplexity Sonar for market research in March 2026.
- Barcode reading in the browser with html5-qrcode and a free UPC database, so retail items skip the vision model.
- Payments through Stripe; 1% of each payment goes to Stripe Climate, by the company's pages.
- An MCP server (Model Context Protocol, a standard way for AI assistants to call outside tools) lets Claude and ChatGPT users price items inside the chat.
Tools named in the sources
Each one opens its page in the Tools tab, with every story that uses it.
Who tried this before Underpriced AI, and why did they fail?
Three companies in our database of failed startups tried to make buying, valuing or selling used goods easier and failed. The values below are from that database and are not independently verified.
Covetly
The promiseA digital inventory for collectors, with market values and trading.
Why it diedUsers had little reason to return, and the platform could not stand apart from eBay.
Selltag
The promiseEasy listing and discovery of second-hand goods in a local marketplace.
Why it diedIt never reached enough buyers and sellers in each area; Wallapop and Facebook Marketplace took the market.
Tradesy
The promisePeer-to-peer resale of designer clothing and accessories.
Why it diedThe RealReal and Poshmark scaled faster, and marketing costs to win both buyers and sellers stayed high.
The failed startups come from our database of 1,749 dead startups, retold here in our own words. Its entries are AI-assisted summaries of public sources, so these cards carry no evidence grade.
What changed
All three tried to be the place where used goods change hands, so each needed many buyers and many sellers at once and had to fight eBay or Facebook Marketplace. Covetly also tried to value collections, but its values needed a market it did not have.
Underpriced AI sells a tool to the seller and leaves the selling to the existing marketplaces. A vision model can now name an object from one photo for a few cents, and sold-price data from eBay can be bought through APIs, so one developer can offer identification and valuation without building a marketplace or a catalogue of his own.
Can one person copy Underpriced AI now?
Yes, with a known user and search pages.
The parts are rented: a vision model, a sold-price API, Stripe and a phone wrapper around a web app. What took work is accuracy on odd items and the search articles that bring visitors. The market already has several similar apps, so a copy needs a narrower group of sellers or better data.
Where it is still open: Sellers of one kind of item with its own markets and price sources: records, books, sports cards, tools, vintage clothing, outside the US and UK eBay markets.
- 1Build for one person you know who does the task every day.
- 2Let the model identify, and take the price from recorded sales, with a backup source.
- 3Measure the model cost of each use early and set the price above it; use cheaper paths, such as barcodes, where they fit.
- 4Write a page for each search your users make, and publish value pages for single items.
What could go wrong for Underpriced AI?
The risks are the mirror image of the causes above.
What is not verified
Every revenue figure on this page, including the US$5,211.76 in the last 30 days, comes from Shipped & Paid, which read a Stripe-verified Indie Hackers revenue page on 30 October 2026 and listed the monthly totals. This page could not open that page, because Indie Hackers blocks Claude agents, and the founder's April 2026 figure of US$589 MRR is also known only through Shipped & Paid. A reader could look for a TrustMRR profile or the founder's own posts with the same figures.
Competition
Similar apps are already on this site: Value AI (an iPhone item price scanner at about US$2.3K a month), PreLoved AI and AutoLister AI (listing writers for Vinted and eBay). The pricing page itself names SoldScan, Pocket Pricer, WorthPoint and crosslisters such as Vendoo and List Perfectly. Shipped & Paid notes that commenters under the launch post called it a copy of another app.
Depends on model and data providers
Each photo scan calls Anthropic's Claude (the founder's March 2026 post gives about US$0.05 a scan) and the price comes from a third-party eBay sold-price API with a backup service. A change in price or access at Anthropic, the data providers or eBay's APIs would change the cost or the quality of every scan.
Filling other marketplaces' forms
The free Chrome extension fills in listing forms on Poshmark, Mercari and other sites from the user's computer, and the user presses Post; the pricing page says the app does not post to other marketplaces on its own. Whether each marketplace's terms allow form-filling extensions is not discussed in the sources.
Counters and reviews
The home page shows '5,900+ resellers have priced $2.8M+ of items' and '4.9 from 9 reviews' with named reviewers. Both are the company's own numbers, and the US$2.8 million is the value of items priced, not revenue. The App Store shows 4.6 from 29 ratings.
Unexplained 'investor forecasts dashboard'
The founder's March 2026 Hacker News post lists an 'investor forecasts dashboard with company valuations' among things shipped that week. No source names an investor or a funding round, so the business is described here as bootstrapped.
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.
- D Shipped & Paid, case page: Underpriced AI, an AI item scanner and pricing tool for resellers at $5,212 in the last 30 days (Stripe-verified on Indie Hackers)Read in full on 6 November 2026. Source for the 30-day figure, the January to September total, the founder's quotation and the growth channels. It retells an Indie Hackers page that this pipeline may not fetch.
- D Shipped & Paid, data.json entry for Underpriced AI (generated 2 November 2026)Read the Underpriced AI entry, downloaded by the pipeline on 6 November 2026. Source for the monthly totals, the April 2026 founder update and the organic session counts.
- C Underpriced AI home pageRead in full on 6 November 2026. Source for the usage counter, the reviews, the sold-price sources and Stripe Climate.
- C Underpriced AI pricing pageRead in full on 6 November 2026. Source for the pricing table, the named competitors and what the app does not do.
- C About Underpriced AIRead in full on 6 November 2026. Source for the two co-founders and the use of Anthropic's Claude.
- C Underpriced AI llms.txtRead the sections on the scan, the pricing sources, the technology and the MCP server, 6 November 2026.
- C Hacker News, 14 March 2026: Show HN: I added barcode scanning to my AI pricing app, 92% cheaper per scan (fkratzer)Read the founder's full post text in the Hacker News search API result that the pipeline downloaded on 26 October 2026. Source for the per-scan costs and the stack.
- C App Store: Underpriced AI, by Underpriced AI LLCRead the rating, the age rating and the seller, 6 November 2026.
- C Internet Archive copy of underpricedai.com, 30 December 2025Read in full. The earliest capture in the archive's index; source for the launch month.
- C Database of failed startups, local exportLocal export. AI-written summaries, not independently verified. Source for the failed predecessors.
Run this company? Send corrections or a verified figure to aiolum@livyden.com