Does the editor understand file structures?

No. It edits raw bytes and does not validate headers, checksums, offsets, or application-specific formats.

Can I compare files of different sizes?

Yes. Differences within the shared range and bytes beyond the shorter file are counted.

Are files sent to NanToo?

No. File contents stay in the browser; normal page-access analytics may still apply to the page itself.

Developer Tools

Online Binary and Hex Editor

Inspect and edit binary files as hexadecimal bytes, compare two files, jump to differences, and download edits without uploading files to a server.

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About Online Binary and Hex Editor

Inspect and edit hexadecimal bytes

Load a file into tab A or B, select any HEX cell, and enter one or two hexadecimal digits. The ASCII column is a display aid; bytes remain the source of truth.

Compare two binary files

When both files are loaded, differing offsets are highlighted and listed. Files of unequal length show out-of-range values after the shorter file ends.

Local processing and safe copies

Files are read in your browser and are not uploaded. Download creates a new file; it does not overwrite the original. Keep a backup before editing important data.

Frequently asked questions

Q. Does the editor understand file structures?: No. It edits raw bytes and does not validate headers, checksums, offsets, or application-specific formats.
Q. Can I compare files of different sizes?: Yes. Differences within the shared range and bytes beyond the shorter file are counted.
Q. Are files sent to NanToo?: No. File contents stay in the browser; normal page-access analytics may still apply to the page itself.

Sources and specifications

MDN: File API

Questions or feedback? Contact NanToo

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