File Structure Viewer
See what’s inside any file — header, body, footer, metadata and hidden trailing data, each labelled with its offset, length and meaning, plus a byte-map and hex view. Nothing is uploaded.
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Drop any file to see its structure
Images, PDFs, archives, executables… — read in your browser, never uploaded
How to use
- Drop any file in, or tap the box to choose one. The tool reads its first bytes to detect the real format (not just the extension) and breaks it into sections.
- Each section is labelled and categorised — signature, header, metadata, body, footer, checksum or trailing data — with its offset, length and share of the file. Click a section (in the list or the colour byte-map) to see its raw bytes in the hex view.
- Text that isn’t readable is shown as its data type and hex instead. Press Download report to save the full section table as JSON for your own analysis.
FAQ
Which file formats does it understand?
It parses the structure of common formats in detail — JPEG, PNG, GIF, BMP, WebP/RIFF and WAV, ZIP (and ZIP-based files like DOCX/XLSX/JAR), GZIP, PDF, ELF, Windows PE (EXE/DLL), MP3/ID3 and ICO — and recognises many more by their magic bytes (7z, RAR, MP4, FLAC, OGG, SQLite, TIFF, PSD, WebM and others), showing their signature, body and statistics. Anything unknown still gets a full byte-map, hex view and data stats.
Can it show data that isn’t supposed to be in the file?
Yes — that’s a highlight. Bytes that fall after a format’s standard end (for example, data appended after a JPEG’s end marker or a ZIP’s central directory) are flagged as “trailing data”, and any region the parser can’t attribute is marked as unclassified. It’s a quick way to spot hidden or leftover data.
Is my file uploaded anywhere?
No. The file is read and analysed entirely in your browser — it never leaves your device, so the tool works offline and stays private, even for sensitive files. Only you ever see the bytes, and the report you download is generated locally.