Dynamic Cache

CorsProxy caches responses at the edge to reduce latency and protect origin services from repeated requests.

Note: Cache is stored per data center, not globally. Users in different regions will have separate caches, which means initial requests from a new region will fetch from the origin before being cached locally.

Default Caching Behavior

CorsProxy uses two caching paths depending on the request:

Tiered cache (GET/HEAD)
- Uses Cloudflare tiered cache.
- Default TTL: 1 hour.
- Applies to GET/HEAD requests when caching is eligible.
Cache API (POST + feature requests)
- Used for POST requests (when cacheable), extract/convert requests, or when a TTL override is used.
- Default TTL: 1 hour unless overridden.

TTL Overrides

You can override cache duration with the ttl parameter.

Format: integer seconds (e.g. 300, 3600).
Requires: a valid API key and a Business plan.

Example (5 minutes):

https://corsproxy.io/?url=https://example.com/data&key=YOUR_API_KEY&ttl=300

Cache Eligibility Rules

Caching is bypassed when any of the following apply:

Request includes Authorization or Cookie headers.
Response includes Set-Cookie or WWW-Authenticate headers.
POST content type is unsafe or unknown (e.g. application/x-www-form-urlencoded, multipart/form-data).
Cache is disabled for the current plan or request.

Cache Keys

Cache keys are derived from:

Normalized target URL
HTTP method
POST body hash (for POST cache keys)
API key (for Cache API entries)
TTL override (when provided)
Feature variants (extract/convert)

This keeps raw responses separate from converted or extracted outputs and isolates caches per key when required.

Cache Headers

CorsProxy includes cache-related headers in responses:

Header	Description
`X-Cache-Status`	`HIT`, `MISS`, or `BYPASS`
`X-Cache-Read`	Cache API read result (`hit`, `miss`, `no-caches-api`, etc.)
`X-Cache-Write`	Cache API write result (`saved`, `put-failed`, etc.)
`X-Cache-Skip`	Reason caching was skipped
`X-Cache-Body-Hash`	Body hash used for POST cache keys

Enable debug mode for extra diagnostics:

https://corsproxy.io/?url=https://example.com/data&debug=1

Debug headers include:

X-Cache-Path (tiered-cache, cache-api, bypass)
X-Cache-Key-Url
X-Cache-Key-Hash

Usage Examples

Default caching (1 hour):

https://corsproxy.io/?url=https://example.com/data

POST caching (cacheable content type):

https://corsproxy.io/?url=https://example.com/graphql

Custom TTL (Business plan + API key):

https://corsproxy.io/?url=https://example.com/data&key=YOUR_API_KEY&ttl=900