Replit
Build your own app with Replit Agent: plan before it builds, roll back bad changes, keep keys and real data safe, then publish without surprise bills.
Start: What Replit is and where things liveAbout Replit
Replit is a browser-based place to build and publish apps by describing them to Replit Agent. Agent plans the work, writes the code, runs the app in Preview and saves checkpoints you can roll back to. A project can hold a database, file storage and secrets. You publish with Autoscale, Static, Reserved VM or Scheduled deployments, and Agent Modes plus usage limits control what you spend.
Best for: Indie founders, freelancers and first-time builders who want a working app without setting up servers.
Good for
- Going from an idea to a running app in Preview
- Trying changes safely with checkpoints and Rollback here
- Adding a database, file storage and secrets without extra setup
- Publishing to a .replit.app address or your own domain
Where people slip
- Trusting Agent's summary without testing the app in Preview
- Pasting API keys into the chat instead of the Secrets form
- Expecting a checkpoint rollback to undo changes in your production database
- Forgetting that a published app needs its own production secrets
Does Replit still have Assistant?
No. Replit deprecated Assistant in December 2025. Use Agent's Plan mode to talk through ideas without changing files, and Build mode to make changes.
What is the difference between Free, Power and Max mode?
They are Agent Modes, picked in the prompt box. Free uses your included allowance. Power balances speed and capability and uses monthly credits. Max is the most capable, for hard problems. Replit warns you before a request moves into a paid mode.
Does rolling back a checkpoint restore my data?
Rollback here restores your files and Agent's chat context. Your development database comes back only if you pick Database under Additional rollback options. A checkpoint rollback never restores your production database.
Can Replit use my project to train its models?
Replit says it uses content you provide to improve its models. Pro users can opt out with Model Improvement in Settings, under Personalization. Replit does not train on Enterprise customer content.
Why does my app work in Preview but break after publishing?
Secrets from the Project Editor don't carry over to the published app. Add them as production app secrets in the Publishing settings, then read the Logs tab. Apps that only listen on localhost also fail once published.
Checked against Replit's own docs on 2026-11-09.
Basics
Know what Replit is, build a first app with Agent, and check what it built in Preview.
New to Replit? Start here. Already use it? Skip to the next milestone.
0 of 2 lessons completeBrief the Agent and roll back
Plan a change before Agent builds it, and undo a bad change with checkpoints.
0 of 2 lessons completeSecrets, databases and user data
Keep keys in Secrets, keep real data out of testing, and keep development and production data apart.
0 of 2 lessons complete