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Caching

Cache-Control

IANA permanent response RFC 9111 reached by regulation 3 spellings

Declared by 109 providers across 3568 published specification files in the APIs.io network.

What this header is for, and how to use it →

A count here is providers whose published contract declares this header — not providers who send it. Response headers set at the edge rarely appear in an OpenAPI at all, so a low number can measure documentation practice rather than deployment.

Spelled 3 ways

HTTP field names are case-insensitive (RFC 9110 §5.1), so every spelling below is the same header on the wire. A contract is not the wire: generated clients key off the string, and a developer reading two of these sees two different headers.

Cache-Controlcache-controlCACHE-CONTROL

Reached by regulation

Basis: evidentiary. No law names this header; it is the deployed control for an obligation that regulation does impose. Observable at the edge, without credentials.

hipaa glba

The registry

Statuspermanent
ReferenceRFC 9111, Section 5.2: HTTP Caching

Providers declaring it (109)

73-strings aib-group-uk aldermore amazon-s3 an-api-of-ice-and-fire apache-couchdb api-snap appsmax-rest-api-v1 aws-s3 backpack bank-of-ireland-uk bank-of-scotland bazaarvoice bird britive ccp-games chili-piper cloudflare-r2 co-operative-bank cohere confident-cannabis confident-lims constructorio coventry-building-society cyclecalcs daring-foods deliverect docker dream-sports electric-sql engineering-platform etoro euler eve-online extreme-networks ezoic factset first-direct gb-bank halifax heyform honeycomb-io hopper-com jp-morgan-chase just-eat keboola kimi-moonshot leeds-building-society limble-cmms limitless-ai linkpeek lloyds-banking-group mem mercedes-me method-financial methodfi metro-bank mettle microsoft-azure monument-bank moonshot-ai nationwide-building-society netbird nhost oauth open-banking-uk opengov openrelay oracle oracle-hospitality paragon-bank peertube planomy-tax-data podman primitive principality-building-society process-street pruna-ai qfex recognise-bank render rentberry roadsync rocket-lawyer safello sageox salesforce saml santander-uk secure-trust-bank shawbrook-bank shyft skipton-building-society spectro-cloud starling-bank superrare tenable totalis tradeverifyd tsb-bank understudy-labs userpilot usertesting virgin-money-uk vtex waodao weatherbys-bank worldcat xquik-api

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