API Rate Limiting
Restricting the number of API requests a client can make within a specified time period.
Definition
API rate limiting controls how many requests a client can make to an API within a given timeframe. Limits protect servers from overload, prevent abuse, ensure fair usage across customers, and manage infrastructure costs.
Rate limits are typically expressed as requests per second, minute, or hour. When exceeded, APIs return error codes (often 429 Too Many Requests) until the limit resets.
Why It Matters
Rate limiting is essential for API stability and fair resource allocation. Understanding rate limits helps developers build applications that gracefully handle restrictions.
For API providers, well-designed rate limits balance accessibility with infrastructure protection.
Examples in Practice
A social media API limiting free tier users to 100 requests per 15-minute window.
Implementing exponential backoff in application code to handle rate limit responses gracefully.
Enterprise API tiers offering higher rate limits to accommodate business-critical integrations.