HTTP Status Codes — When to Use 200, 404, 429, 500

Complete HTTP status code guide for REST APIs. When to use 200 vs 204, 400 vs 422, 401 vs 403, 404 vs 410, 429 rate limiting, and 5xx errors. Quick decision guide + searchable by code or description.

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Frequently asked questions

Request created a resource?

201 Created

Request succeeded, no body?

204 No Content

Async job was queued?

202 Accepted

Not logged in / bad token?

401 Unauthorized

Logged in but no permission?

403 Forbidden

Resource doesn't exist?

404 Not Found

Duplicate / constraint conflict?

409 Conflict

Validation failed (bad value)?

422 Unprocessable Content

Missing field / bad JSON?

400 Bad Request

Rate limit hit?

429 Too Many Requests

Server crashed / unhandled error?

500 Internal Server Error

Downstream service down?

502 Bad Gateway

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