---
title: "Rate Limit — Definition | FourSight Glossary"
url: https://foursight.cloud/glossary/rate-limit
description: "A cap on how many requests a client may make to an API in a given time window. Exceeding the limit typically returns HTTP 429 Too Many Requests."
lang: en
---

Back to glossary: https://foursight.cloud/glossary

Web & Networking

# Rate Limit

A cap on how many requests a client may make to an API in a given time window. Exceeding the limit typically returns HTTP 429 Too Many Requests.

Source

- IETF — RFC 6585 §4 — 429 Too Many Requests (https://datatracker.ietf.org/doc/html/rfc6585#section-4)

## Related terms

HTTP Status Codes (2xx / 4xx / 5xx)

Three-digit response codes returned by HTTP servers.
https://foursight.cloud/glossary/http-status-codes

Timeout

The maximum time a client waits for a response before giving up.
https://foursight.cloud/glossary/timeout

DNS (Domain Name System)

The internet's address book — translates human-readable domain names like foursight.cloud into IP addresses…
https://foursight.cloud/glossary/dns

A Record

A DNS record that maps a hostname to an IPv4 address (e.g.
https://foursight.cloud/glossary/a-record

AAAA Record

Maps a hostname to an IPv6 address.
https://foursight.cloud/glossary/aaaa-record

CNAME Record

An alias DNS record that points one hostname to another (e.g.
https://foursight.cloud/glossary/cname-record

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