What is Rate Limiting?

Rate limiting restricts the number of API requests a client can make within a specified time window.

How it works

APIs enforce rate limits to protect infrastructure capacity and prevent abuse. Standard HTTP responses use 429 Too Many Requests alongside X-RateLimit-Limit, X-RateLimit-Remaining, and Retry-After headers.

Common mistakes

  • Omitting Retry-After header on 429 responses
  • Not documenting rate limits in OpenAPI security schemes