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DEVELOPER BENCH
Find a common MIME type for a supplied file extension using a small bundled reference map and clearly report unknown extensions.
WHAT THIS DOES
Runs entirely in your browser.
/tools/mime-type-lookupmime-typev4.0.0LOCAL · LOCAL RUNIMPLEMENTED — This workbench is functional in the current release.Presets for this workbench
No preset yet. A preset stores the values in this form — never the result — and only for workbenches that run entirely in your browser.
Collections
Saved on this device only. Turn on sync to carry them to another device.
BATCH / ONE VALUE PER LINE
Up to 200 lines, one at a time, in this browser. Each line takes the place of extension and everything else stays as you set it. Nothing is uploaded, and the row limit is not exceeded silently.
METHOD / LOCAL RUN
A local case-insensitive extension map returns common conventional MIME values and a no-match state for values outside the bundled set.
Boundary: The map is intentionally limited. MIME type is not established by extension alone, and this does not inspect a file, response header, upload, or security policy.
The calculation or transformation runs in your browser using the values entered above. No input is sent to UtilityForge for this tool.
EXAMPLES / LOCAL RUN FIXTURES
FAQ
The map is intentionally limited. MIME type is not established by extension alone, and this does not inspect a file, response header, upload, or security policy.
No. This published tool runs locally in your browser. UtilityForge does not send the values entered in this workbench to a server.
No. This workbench runs in the page: File extension are read by the code your browser already downloaded, and UtilityForge receives neither the values nor the result.
Yes, and it is enforced rather than advertised: File extension (32 characters). The limit is a browser input limit on a tool that runs on this device, so nothing is truncated after being sent anywhere.
RELATED TOOLS
LOCAL — Runs entirely in your browser.
COMMON USE CASES / SOURCE NOTE
Last reviewed:
Source information: Small bundled extension-to-MIME reference map. No file is read, uploaded, sniffed, or associated with a server response.