Replit is a platform from Replit, Inc. for building software with an AI agent: a program that uses large language models (neural networks trained on large amounts of text and code) to plan and write code from a request in natural language. A user describes an app or a website, and the Replit Agent writes the code, changes it on request and publishes the result.
The project lives in Replit's cloud workspace, which works in a web browser, in a desktop app for macOS and Windows, and in mobile apps for iOS and Android. Replit adds built-in services with no setup: authentication (user login), a database, hosting and monitoring. More than 100 integrations connect an app to services such as OpenAI, Stripe and Google Workspace. Plan mode lets the agent plan before it builds. Replit warns that the agent's behavior is probabilistic, so it can make mistakes.
Replit is a hosted service sold by subscription. Each paid plan includes a monthly amount of credit for AI models; further use is billed by the effort of each task. A Free Mode allows some chat and creation at no cost.