About The MIME Type Lookup

The MIME Type Lookup maps common file extensions to content types and can also reverse lookup common extensions from a MIME value. It is useful when you are checking upload rules, response headers, API payloads, static asset configuration, or file handling behavior.

The lookup runs from a local browser map, so it is fast and does not contact a server for the value you enter. The map covers common web and document types, but it is still a quick reference rather than a complete registry.

How to Look Up MIME Types Online

1. Enter a file extension such as .svg or json, or enter a MIME type such as application/json.
2. Click Lookup.
3. Review the matching MIME type, common extension, or related extensions.
4. Copy the output when you need it for headers, validation rules, server config, or documentation.

Choosing Inputs Correctly

File extension: You can include or omit the leading dot. For example, .png and png are treated the same.

MIME type: Enter the full type/subtype value, such as image/png or text/css, when you want common extensions for that content type.

Common Use Cases

• Checking the expected Content-Type value for a static asset.
• Reviewing upload allowlists and file validation rules.
• Debugging API responses, downloads, and browser rendering issues.
• Adding quick MIME references to docs, tickets, or server configuration notes.

Quick FAQ

Does this inspect the actual file contents?
No. It maps extensions and MIME strings; it does not read file bytes or verify magic numbers.

Can a file extension be trusted for security?
No. Extensions and MIME headers can be wrong or spoofed. Sensitive uploads need content inspection and policy checks.

What if a MIME type is not found?
Check spelling, remove leading dots or parameters, and confirm the type with an authoritative registry or application docs.

How can the wrong MIME type break things?
Browsers and APIs may render, download, reject, or cache files differently when the content type is wrong.