File Format Inspector

Compare a file name's extension with its real type from the first bytes; flags executables disguised as documents or images.

Read a GIF's version, width, height and global colour table size from its first 13 bytes.

Parse a gzip header: method, flags, modification time, original file name, OS and compression hint.

Read a JPEG's width, height, components and baseline/progressive mode by walking its markers; flags JFIF and Exif.

Identify a file type from the first bytes (hex): PNG, JPEG, PDF, ZIP, ELF, EXE, MP4, SQLite and 40+ more signatures.

Read a PDF's version and header position from its first bytes; flags junk before %PDF- and an invalid version.

Read a PNG's width, height, bit depth, colour type and interlace from its first 33 bytes, and verify the IHDR CRC.

Read a WebP's width, height, lossy/lossless/extended format, alpha and animation flags from its first 30 bytes.

Parse a ZIP's first entry header: name, method, sizes, CRC, encryption, and zip-slip path or executable-name risks.