Both

HTTP Cache-Control Header

Specifies caching directives for both requests and responses. Controls how and for how long content is cached by browsers and intermediate caches.

Purpose

Optimizes performance by controlling caching behavior, reducing redundant requests and server load.

Cache-Control: no-cache Cache-Control: no-store Cache-Control: max-age=3600 Cache-Control: public, max-age=86400 Cache-Control: private, must-revalidate

Code Examples

See how to use the Cache-Control header in different tools and languages.

curl -I -H "Cache-Control: no-cache" https://api.example.com/resource
curl -I https://api.example.com/resource
# Check Cache-Control header in response

Related Headers

Pragma

HTTP/1.0 header for implementation-specific directives. Mostly replaced by Cache-Control in HTTP/1.1. The most common usage is Pragma: no-cache.

ETag

An identifier for a specific version of a resource. Used for cache validation and conditional requests to avoid re-downloading unchanged content.

If-None-Match

Makes the request conditional. The server responds with 304 Not Modified if the resource's ETag matches the provided value. Otherwise returns the full resource with 200.

Vary

Determines how the response should be cached based on request headers. Ensures caches serve the correct version based on varying request criteria.

Test Your APIs

API Response Time Checker

Test your APIs and inspect response headers in real-time

HTTP Headers Reference

Complete reference of all HTTP request and response headers

cache-control headerhttp cache-controlhttp headers guide