Hex File Viewer
Hex File Viewer reads the first selected file, keeps at most its first 65,536 bytes, and prints two lowercase hex characters per byte with a line break after every 16 bytes. It has no offsets, ASCII column, byte grouping, search, parser, or indication that additional bytes were truncated, so it is a lightweight prefix view rather than a forensic hex editor.
Runs locally — files stay on your deviceHow much of a file is shown?
At most the first 64 KiB (65,536 bytes) of the first selected file.
Hexadecimal is a direct byte notation
Each byte ranges from 0 to 255 and is represented by exactly two base-16 digits from 00 through ff.
How it works
The first file is buffered, sliced to 65,536 bytes, converted byte by byte, and split into lines of 32 hex characters.
Key concepts
Sixteen bytes per line
A full line contains 32 hex characters.
Prefix only
Later content and possible appended data are not displayed.
When to use it
- Look for a familiar signature near a file's start.
- Inspect a small binary prefix.
- Copy a short hexadecimal representation.
When not to use it
- Do not use it to inspect data beyond 64 KiB.
- Do not treat visible signatures as complete validation.
- Do not edit or reverse-engineer complex structures with this view.
Worked examples
PNG prefix
- Input
A typical PNG- Expected output
Begins 89504e47...
A signature is a clue, not full validation.
Tiny file
- Input
3 bytes- Expected output
6 hex characters
No padding bytes are added.
Large archive
- Input
10 MB ZIP- Expected output
First 64 KiB
Most bytes are omitted.
Common mistakes
Assuming the whole file is visible
Output stops after 65,536 bytes. Correction: Use a full hex tool for exhaustive work.
Looking for offsets
Lines have no address labels. Correction: Count carefully or use an editor with offsets.
Equating a header with safety
Polyglots and malformed files can share signatures. Correction: Parse and scan untrusted content.
Best practices
- Keep the 64 KiB limit in mind.
- Use a format-aware parser for conclusions.
- Compare against a trusted specification.
Related operations and differences
Add Prefix to Filenames
Choose Add Prefix to Filenames when you need to add a prefix to selected filenames.; use Hex File Viewer specifically for hex view.
Add Suffix to Filenames
Choose Add Suffix to Filenames when you need to add a suffix before every extension.; use Hex File Viewer specifically for hex view.
Compare Two Files
Choose Compare Two Files when you need to compare two files securely by SHA-256.; use Hex File Viewer specifically for hex view.
File Checksum Comparator
Choose File Checksum Comparator when you need to compare a file digest with an expected checksum.; use Hex File Viewer specifically for hex view.
File Hash Calculator
Choose File Hash Calculator when you need to calculate a local cryptographic file digest.; use Hex File Viewer specifically for hex view.
File Size Calculator
Choose File Size Calculator when you need to inspect exact and human-readable file sizes.; use Hex File Viewer specifically for hex view.
Limitations and privacy
- First file and first 65,536 bytes only.
- No offset, ASCII, search, grouping controls, parser, editing, export, or explicit truncation marker.
- The full file is initially buffered before slicing.
Processing happens in this browser. Selected file contents are not uploaded by this tool.
Downloads and copied results remain on this device; handle them according to their sensitivity.
Frequently asked questions
Can it modify bytes?
No.
Are hex letters uppercase?
No, output is lowercase.
How many bytes are on a line?
Up to 16.
Does it show the file end?
Only when the file is no larger than 65,536 bytes.