---
title: "HTTP Status Codes (2xx / 4xx / 5xx) — Definition | FourSight Glossary"
url: https://foursight.cloud/glossary/http-status-codes
description: "Three-digit response codes returned by HTTP servers. 2xx = success, 3xx = redirect, 4xx = client error (bad request), 5xx = server error. Monitoring too…"
lang: en
---

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

Web & Networking

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

Three-digit response codes returned by HTTP servers. 2xx = success, 3xx = redirect, 4xx = client error (bad request), 5xx = server error. Monitoring tools alert on 4xx/5xx codes.

Sources

- IETF — RFC 9110 §15 — Status Codes (https://datatracker.ietf.org/doc/html/rfc9110#name-status-codes)
- MDN Web Docs — HTTP response status codes (https://developer.mozilla.org/en-US/docs/Web/HTTP/Status)

## Related terms

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

MX Record

Identifies the mail servers responsible for accepting email for a domain.
https://foursight.cloud/glossary/mx-record

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