GlossaryWeb ScrapingBeginner

Rate Limiting

Rate limiting restricts how many requests a client can make in a given time, and it is one of the most common defenses scrapers must work around.

Last updated May 28, 2026

Definition

Rate limiting is a server-side control that caps how many requests a single client — usually identified by IP or API key — may make within a time window. Exceeding the limit returns errors like HTTP 429 (Too Many Requests) or triggers temporary blocks.

Working with rate limits

Scrapers respect or circumvent rate limits by pacing requests, adding delays, and distributing traffic across many IPs via rotating proxies. Respecting reasonable limits is also good etiquette and reduces the chance of a hard ban.

Examples

1

An API returning HTTP 429 after 100 requests per minute

2

Adding randomized delays between scraper requests to stay under a limit

Common Use Cases

Preventing server overload
Throttling abusive clients
Designing polite, resilient scrapers

Frequently Asked Questions

It means 'Too Many Requests' — you have exceeded the server's rate limit and should slow down or back off before retrying.
Most limits are per IP, so rotating across many proxy IPs spreads requests and keeps each IP under the threshold.
What is Rate Limiting? Definition & How to Handle It | ProxyHorizon | ProxyHorizon