Detect Extension and MIME Mismatches

Verify if file extensions match their true internal binary format to detect disguised or corrupted files.

How It Works & Processing Standards

Verify if file extensions match their true internal binary format to detect disguised or corrupted files.

Your input data is never sent to any server and is securely processed on your device.

Current Limits

  • Desktop max file size: 100MB
  • Mobile max file size: 40MB

Detect Extension and MIME Mismatches is a 100% free, browser-based online utility. All calculations and file conversions run locally inside your browser (Local-First) without sending data to remote servers, keeping your documents and inputs strictly private.

How to Use Detect Extension and MIME Mismatches

  1. 1
    Select FilesChoose files to verify.
  2. 2
    Review VerdictInspect verdict table indicating match or discrepancy.

Common Use Cases

  • Detecting executable files renamed with .jpg or .pdf extensions to bypass upload filters
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