File Type Detector
Detect the likely real format of a file using its extension, browser MIME type, and binary signature bytes. This browser-based file type detector helps identify files that may not match their displayed extension.
Upload a file to detect its type
This tool checks the file extension, browser MIME type, and magic bytes to estimate the real file format.
Drag and drop your file here
or
Supports common document, image, archive, audio, video, and executable formats.
Detection summary
Estimated type and supporting file details.
No detection result yet. Upload a file to inspect its type.
Detection signals
These signals are compared to estimate the most likely file type.
Upload a file to compare extension, MIME type, and signature bytes.
Raw signature preview
First bytes of the file in hexadecimal and ASCII form.
Upload a file to inspect its leading bytes.
What does a file type detector do?
A file type detector examines multiple clues about a file, including its extension, MIME type, and magic bytes, to estimate its true format. This is useful when a file may have been renamed, mislabeled, or downloaded without a trustworthy extension.
How this tool identifies file types
This tool compares three signals: the visible file extension, the MIME type reported by the browser, and the leading signature bytes read from the file itself. When these signals agree, the result is more reliable.
When they disagree, the tool highlights a possible mismatch so you can inspect the file more carefully before opening or sharing it.
Private browser-based detection
The file stays in your browser while this detector inspects it. No upload is required, which makes it practical for quick private checks on documents, images, videos, archives, executables, and other local files.
Common use cases
- • Check whether a file matches its extension
- • Identify common file formats from magic bytes
- • Inspect suspicious or mislabeled downloads
- • Validate file types before processing them
- • Confirm whether a renamed file still matches its content