Developer
Processed locallyFile Signature Inspector
Identify common file formats from magic bytes rather than their names.
Tool options · presets, sharing & more
Presets & sharing: options only, never files, text or passwords. Undo/redo: editable form values, not file selection or generated results.
How to Use File Signature Inspector
Choose the file or files for the operation; Base64 decode uses pasted input.
Set the options and arrange multiple files using the arrows if needed.
Run the operation and inspect its output or report.
Copy the text or download the resulting file(s).
What This Tool Does
Identify common file formats from magic bytes rather than their names. Detects common formats from leading bytes. Unknown signatures and polyglot files require further inspection; this is not a malware scan.
Common Use Cases
This tool processes files and input in this browser tab. Its processing code does not upload them to a server. Loading this page and fetching uncached app files uses an internet connection. Optional usage analytics requires your consent and excludes input, filenames, passwords and generated content. Form undo history and result transfers stay in session memory. Explicitly saved presets contain approved settings only.
Offline use is not verified for this tool. Keep an internet connection available to load its page, code and any additional dependencies.
Frequently Asked Questions
What should I check before using the result?
Detects common formats from leading bytes. Unknown signatures and polyglot files require further inspection; this is not a malware scan.
Are my files or inputs uploaded?
No. This tool processes selected files and entered data locally in your browser. Only the page and its supporting code are downloaded.
Does this tool work offline?
Offline use is not verified for this tool. Keep an internet connection available to load its page, code and any additional dependencies.