Binary Editor

About this tool

Load any file and edit hexadecimal (HEX) and ASCII inline. Modified cells are highlighted in red. Everything runs entirely in your browser—no uploads. Search stays responsive even around 7–20 MB thanks to Web Workers, debouncing, and result caps.

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Edit mode
Edit
Selection / change
Selection: — Modified: 0
0 / 0
Offset HEX ASCII

How to use

  1. Load a file via File—processing stays in the browser.
  2. Click HEX or ASCII cells to edit inline. HEX expects two digits (0-9A-F); ASCII takes one character.
  3. Search toggles between ASCII and HEX. HEX accepts "DE AD BE EF" or "DEADBEEF"; ASCII can be case-sensitive or insensitive.
  4. Insert/Delete modifies one byte at the caret.
  5. Save downloads the current buffer.

Notes (freeze prevention)

  • Search runs in a Web Worker, so the UI stays responsive.
  • Input is debounced (~180 ms) so rapid typing cancels previous searches.
  • Up to 500 hits are listed; excess hits show a trailing +.
  • Performance is solid around 7–20 MB. For larger files reduce "Visible rows" to keep scrolling smooth.

Notes

  • Opening another file discards unsaved edits—save first if necessary.
  • The ASCII column accepts printable characters only; other bytes display as ..