🔬 Hex Dump Viewer – Inspect Raw Binary Data in Your Browser
A hex dump is a side-by-side view of binary data presented in three columns: a byte offset, the hexadecimal value of each byte, and a printable-ASCII representation where non-printable bytes are shown as dots. It is the output format produced by classic command-line tools such as xxd, hexdump -C, and od. This browser-based viewer gives you the same capability without installing anything — all processing happens locally in your tab.
Who Uses Hex Dump Viewers?
Hex dump viewers are essential tools for software developers, security researchers, forensic analysts, and system administrators who need to look past a file's extension and examine what is actually stored on disk. Common scenarios include:
- Identifying unknown files by reading their magic bytes — the fixed byte sequence at the very start of a file that determines its true format.
- Debugging encoding issues — for example, confirming whether a text file contains a UTF-8 BOM (
EF BB BF) or CRLF line endings (0D 0A). - Analysing binary protocols — inspecting network payloads, serialised data structures, or firmware images at the byte level.
- Reverse engineering — locating strings, headers, and field offsets inside compiled binaries or proprietary file formats.
- Education — visualising how text characters, integers, and other data types are stored in memory.
Three Input Modes
File Upload
Drag and drop any file onto the upload area or click to browse. The tool reads the file locally using the browser's FileReader API — the bytes never leave your device. Files up to 50 MB are supported. For larger files, use the Start Offset and End Offset fields to focus on a specific byte range without loading the entire file into the viewport.
Text Input
Paste or type any plain text. The tool encodes it using TextEncoder (UTF-8) and immediately shows the hex dump. This is a quick way to see exactly how characters — including multi-byte Unicode sequences — are stored as bytes.
Hex String Input
Paste a raw hex string such as a captured network packet, a hash value, or a binary payload copied from a debugger. The viewer accepts space-separated (89 50 4E 47), colon-separated (89:50:4E:47), or continuous (89504E47) formats and renders the structured dump instantly.
Display Options
The Bytes Per Row setting controls how many bytes appear in each row (default 16, matching xxd). Narrow values such as 8 are useful for visualising 64-bit data structures. Wide values such as 32 or 64 give a denser view suitable for scanning large regions quickly.
Offset Base toggles between hexadecimal offsets (0x00000010) and decimal offsets (16). Decimal mode is useful when cross-referencing with file-format specifications that describe field positions in bytes.
Magic-Byte File-Type Detection
The viewer compares the first 16 bytes against a library of 40+ well-known signatures covering PNG, JPEG, GIF, PDF, ZIP, GZIP, ELF, Windows PE, SQLite, and many more. The detected type is shown as a coloured badge above the dump. This identification works even when a file has been renamed or its extension removed.
| File Type | Magic Bytes (hex) | First ASCII chars |
|---|---|---|
| PNG Image | 89 50 4E 47 0D 0A 1A 0A | .PNG.... |
| JPEG Image | FF D8 FF | ÿØÿ |
| PDF Document | 25 50 44 46 | %PDF |
| ZIP / DOCX / JAR | 50 4B 03 04 | PK.. |
| ELF Binary (Linux) | 7F 45 4C 46 | .ELF |
| GZIP Archive | 1F 8B | .. |
Pattern Search & Highlighting
Enter a search term in the Search & Highlight panel. In ASCII mode, the text is encoded to bytes before searching — useful for finding embedded strings such as Copyright or CREATOR. In Hex Pattern mode, enter the raw bytes to find, such as FF D8 FF E0 to locate a JPEG SOI marker. All matching bytes are highlighted in yellow across both the hex and ASCII columns, and the total match count appears next to the search bar.
Byte Colour Coding
Each byte is coloured by category to make it easy to spot patterns at a glance:
- Grey — null bytes (
0x00), common in padding, C strings, and binary integers. - Orange — control characters (
0x01–0x1Fand0x7F), including tab, carriage return, line feed, and escape. - Blue — high bytes (
0x80–0xFF), which appear in multi-byte UTF-8 sequences, compressed data, and encrypted payloads. - Default text colour — printable ASCII (
0x20–0x7E), matching the character shown in the ASCII column.
Export Options
Click Copy Dump to copy the formatted plain-text dump to the clipboard, or Download .txt to save it as a file. The exported format is compatible with the output of xxd -u, making it easy to paste into bug reports, security advisories, or documentation.
Privacy & Security
All processing happens entirely inside your browser. Files and their byte contents are never sent to any server. You can safely inspect confidential documents, cryptographic keys, and proprietary firmware without any data leaving your machine.