File information inspection
Reads the local file size, MIME, extension, magic bytes, SHA-256, image dimensions, and basic PDF information.
How to use the file information inspector
Files are read and processed only in the current browser; they are not uploaded, the original files are not modified, and nothing is written to persistent storage.
Choose file
Select one or more local files no larger than 20 MiB.
Check information
Compare the file name, extension, browser MIME, magic bytes, digest, and size information.
Export results
Copy or download the JSON inspection report; the original file will not be rewritten.
Limitations and Notes
- Magic bytes can only provide clues about the file type; they cannot guarantee that the file contents are safe or that the file can be opened by all software.
- The tool does not execute files, scan for malicious behavior, or provide comprehensive format forensics or virus detection.
- The maximum size per file is 20 MiB; some complex formats support only basic information.
FAQ
Will the file be uploaded to the server?
No. File reading, digest generation, and metadata parsing all take place in the current browser.
What should I do if the file extension and magic bytes do not match?
Do not trust the file solely based on the inspection results; confirm it further in a trusted environment.
Why does PDF only display basic information?
This tool focuses on file identification and summaries; it does not replace complete PDF parsing, rendering, or content security checks.