File Type Checker

Check likely file type from signatures and metadata; this is not malware scanning or forensic certification.

Choose file

—Detected family

—MIME

—Filename extension

—Detection basis

Choose a fileMagic-byte checks cover common formats only. A signature identifies a container/family, not whether the full file is valid or safe.

Magic-byte, MIME & extension evidence

Inspect the bytes that identify a file instead of trusting its filename. Compare detected signature evidence with the browser MIME type and extension, then copy a compact audit result.

Choose fileOr paste header bytesExpected extensionRead bytes

—Detected type

—Detected MIME

—Extension status

—Header bytes read

Ready.

File handling notes

connects ZIP creation/extraction, archive inspection, GZIP, TAR/TAR.GZ extraction, ZIP merging, multi-ZIP extraction, splitting/joining, duplicate detection, renaming, folder summaries, file inventories, and file-type inspection without requiring a file upload where the browser APIs support the task.

Archive and safety boundaries

Browser memory can limit very large files. TAR extraction supports ordinary TAR/USTAR regular files and directories rather than every PAX/sparse/link edge case. Password-protected or uncommon ZIP compression methods can exceed JSZip support. Normalized download paths do not grant arbitrary filesystem write access.