---
title: rate_limiting
sidebarTitle: rate_limiting
---
# `fastmcp.server.middleware.rate_limiting`
Rate limiting middleware for protecting FastMCP servers from abuse.
## Classes
### `RateLimitError`
Error raised when rate limit is exceeded.
### `TokenBucketRateLimiter`
Token bucket implementation for rate limiting.
### `SlidingWindowRateLimiter`
Sliding window rate limiter implementation.
### `RateLimitingMiddleware`
Middleware that implements rate limiting to prevent server abuse.
Uses a token bucket algorithm by default, allowing for burst traffic
while maintaining a sustainable long-term rate.
### `SlidingWindowRateLimitingMiddleware`
Middleware that implements sliding window rate limiting.
Uses a sliding window approach which provides more precise rate limiting
but uses more memory to track individual request timestamps.