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If-Match

IANA permanent request RFC 9110 reached by regulation 3 spellings

Declared by 106 providers across 11036 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.

If-Matchif-matchIF-MATCH

Reached by regulation

Basis: mandated. The law, or a technical standard the law makes binding, names this header. Visible in a published contract, which is what is counted here.

onc-health-it-certification

Carried by the fhir standard.

The registry

Status	permanent
Reference	RFC 9110, Section 13.1.1: HTTP Semantics

Providers declaring it (106)

8x8 acoustic adobe adobe-premiere adobe-suite aeris akamai alliance-data-systems amazon-cloudfront amazon-s3 arangodb autodesk-fusion azure-ad azure-storage-accounts box bread-financial cadasto cdk-global cerner cint citi clerk-com clio cloudflare-r2 cloudfront commure cubefs cybersource dedaluslabs dotdigital eclipse ehrbase elastic-path engineering-platform equinix etsi forgerock fusebit galileo-technologies genesys glide-apps harness humanitec ibm ilert indykite interhyp intersight jp-morgan-chase lakefs macrometa mastercard microsoft microsoft-azure microsoft-azure-batch microsoft-azure-cost-management microsoft-azure-data-factory microsoft-azure-kubernetes-service microsoft-azure-synapse-analytics microsoft-dynamics microsoft-dynamics-365 microsoft-dynamics-365-business-central microsoft-dynamics-365-sales microsoft-graph microsoft-planner microsoft-power-apps navision newstore nhost ocean-health-systems odata openehr optimizely oracle oracle-cloud oracle-database oracle-goldengate oracle-platforms qliksense qr-code-crafter rook sap-s4hana sap-sales-and-distribution-sd siemens-mindsphere silverflow slashid subspace symphony synack tigris-data twilio uclouvain university-of-washington uphold val-town vendasta veritas-netbackup visma vitagroup vnc wikimedia wikipedia wikisource wiktionary wso2 zuora

Explore

All headers Conditional Requests & Concurrency Guidance on headers.apievangelist.com

Work with this as data

Every header here is available over the APIs.io API and to AI agents over MCP. HTTP Headers is not yet its own endpoint on the v1 API. Reach it through catalog search and the tag graph, or the MCP server.

MCP server

One button, every client — Claude, Cursor, VS Code and the rest.

https://apis.io/mcp

Tools for http headers

3 MCP tools reach this

apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.
resolveTurn a domain, URL or GitHub org into the provider it belongs to.
find_cohortsEvery scored population of providers in the catalog.

All 92 tools →

Call it yourself

curl for this page

Search the catalog

curl "https://apis.io/api/v1/search?q=if-match&limit=10"

Everything under a tag

curl "https://apis.io/api/v1/tags/if-match"

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