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Hex Dump Viewer

Offsets, Hex Bytes, ASCII Column, Magic-Byte File Type and Byte Entropy

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How the Hex Dump Viewer works

This hex dump viewer shows the raw bytes of any file, laid out like xxd or hexdump -C: an offset column, the bytes in hex, and their printable ASCII form. It also names the file type from its magic bytes and measures the entropy. Files are read in your browser and never uploaded.

Reading the hex dump viewer output

Each row starts with the offset of its first byte in hex. The middle shows 16 bytes as pairs of hex digits, split into two groups of eight for easier counting. The right-hand column shows the same bytes as characters, with a dot for anything that is not printable. Text strings, headers and padding stand out quickly this way.

Magic bytes

Most formats begin with a fixed signature. PNG files start 89 50 4E 47, PDFs start %PDF, ZIP-based formats including DOCX and JAR start PK, and Windows executables start MZ. The hex dump viewer checks these, so a file with the wrong extension is easy to spot.

Entropy

Entropy measures how unpredictable the bytes are, from 0 to 8 bits per byte. Plain text sits around 4 to 5. Compressed or encrypted data is close to 8. A high reading in a file that should be text or an image suggests embedded compressed or encrypted content.

FAQ

How much of the file is shown?

Up to 64 KB from the start offset, to keep the page responsive. To look further into a large file, type an offset in hex, such as 1F400, and the dump starts there. The size, type and entropy always describe the whole visible range.

Can I edit bytes here?

No, this viewer is read-only. It is meant for inspecting headers, finding strings and checking what a file really is. For editing, use a desktop hex editor such as ImHex or HxD, which can also save changes.

Is it safe to open a suspicious file?

Yes. The file is only read as bytes and displayed as text; nothing is executed, rendered or uploaded. That makes a hex dump a reasonable first look at an attachment you do not trust, though a sandbox or scanner is still the right place for full analysis.

See also: all Security & Identifiers tools, Dev Utilities, Formatters & Validators, Data & Encoding, SEO, Accessibility, AI.

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