Why it matters
When a file won't open, an upload is rejected or a download looks suspicious, the answer is in the bytes: the first few say what the file really is, whatever its name, and the structure shows whether it's complete or damaged.
This inspector reads the file on your device and shows the hex, the detected type and a walk through its structure, such as the chunks in a PNG or the entries in a ZIP. The entropy chart shows compressed or encrypted regions, and the data inspector reads any value at the offset you click.
How it works
- InputA file from your device
- In your browserRead byte by byte, format detected
- OutputA hex view, structure, entropy and strings
Where it fits in a designer's workflow
- Plan
- Design
- Build
- Test
- Launch
By the numbers
Show the numbers as a table
| File | Bytes | Bits per byte |
|---|---|---|
| styles.css (text) | 37352 | 5.319 |
| styles.css gzipped | 9383 | 7.978 |
| Tool icon (SVG) | 401 | 4.968 |
| Sample photo (JPEG) | 38778 | 7.975 |
How to use it
- Choose a file, or try the sample PNG.
- Read the detected type and structure.
- Click a byte to read the values starting there.
- Search for text or hex, or browse the strings.
FAQ
How does it know the file type?
Most formats start with a fixed 'magic number', such as 89 50 4E 47 for PNG or 50 4B 03 04 for ZIP. The extension is ignored.
What's entropy?
How random the bytes look, from 0 to 8 bits per byte. Near 8 means compressed or encrypted; text and code are usually 4 to 5.
Can it edit files?
No. It's read-only, so nothing can be damaged.
Is the file uploaded?
No. It's read in your browser, up to 64 MB.
