Create sound effects by drawing volume and pitch sequences, using the 8 waveforms to choose from.
Right-click to remove steps in the sequence. Hold shift to only change the waveform. 
Adjust sound duration (speed), pitch range, or snap pitch to the chromatic scale. 

When you are done editing, exports all your sounds to mp3 or wav audio files. 
Or save your program as text data for future edits.


  • space: play current sound
  • up arrow: navigate to previous sound in the list
  • down arrow: navigate to next sound in the list
  • cmd+up arrow: move selected sound up in the list
  • cmd+down arrow: move selected sound down in the list
  • enter: edit selected sound name
  • backspace / delete: delete selected sound
  • cmd+z: undo
  • shift+cmd+z: redo 
  • cmd+c: copy current sound to a new sound
  • cmd+s: save program data to a text file (to reload it: drag&drop this file on Bleeper)
  • cmd+e: export all sounds to mp3 or wav (a menu will pop up)
  • cmd+n: new program (delete all sounds)

Bleeper is the official SFX creation tool for Pixelbox

Rated 4.9 out of 5 stars
(49 total ratings)
AuthorCedric Stoquer
TagsAudio, Music Production, pixelbox, Sound effects, Soundtoy


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Great Work! any plans for a Stand Alone mode? would love to run on my raspberry pi or just windows offline to make wavs to manipulate in my DAW

(2 edits) (+1)

so awesome...

maybe a bug:
after importing a json i cant duplicate sounds anymore (firefox 103.0 on an old mac)

EDIT: shortcuts dont work for me at all on mac. this might be an thing tho.

runs great on ubuntu btw.


dang, now this is cool.




Make a standalone version I can run on my desktop without a browser and I'll buy!


whoa this ruuules


Great program! Would love to see a loop feature!


very cool. seems incredibly useful for generating novel β€˜8-bit’-styled effects


are these sounds able to be used for games, commercial or otherwise?


Yes, sounds made with Bleeper are free to use without any restrictions in any projects, commercial or otherwise.


this helps ALOT


This is VERY VERY NIIIIIIIIIIICE πŸ‘πŸ‘πŸ‘πŸ‘πŸ‘πŸ‘πŸ‘πŸ‘πŸ‘πŸ‘πŸ‘πŸ˜πŸ˜πŸ˜πŸ˜πŸ˜

Really cool and useful. Possibly found a bug? I exported something and then was unable to use the "space to play" shortcut. Refreshed the page and it worked again, so no big deal.

This exact same thing just happened to me in Petaporon, which is also by this developer.

(1 edit)

I think this has something to do with the size of the window, as this has happened to me when I had the window at half size, but when it was fullscreen it worked perfectly.

Noted. I'll experiment to see.

Show post...

Really useful!!!--