jsfxr

What it is

jsfxr is an online 8-bit sound maker and sound effect generator. It is a JavaScript port of the original sfxr by DrPetter, which game jam developers have used for years. You pick a preset (pickup or coin, laser or shoot, explosion, power-up, hit or hurt, jump, click, blip), press it until you like the result, adjust sliders for the waveform, envelope, frequency, vibrato and filters, then download the sound as a WAV file.

The source is open, and it can also be used as a JavaScript library to play sounds in web games. A paid Pro version adds more features; the free version is enough for most games.

Is it worth using?

Yes, for retro or stylised games and for jams. It solves the "my game has no sound" problem in minutes, and sound makes a huge difference to how responsive controls feel. For realistic sounds, use recorded effects from freesound or Kenney's audio packs instead.

Tips

• Generate several variants of each effect and play them at random, or vary pitch slightly, so repeated sounds do not become tiring.
• Lower the volume of frequent sounds such as footsteps and shots compared with rare ones.
• Save the settings (it can export them) so you can tweak a sound later.

Licence

Check the site for the current terms on sounds you generate. Sounds made with sfxr-style generators are widely used in commercial and jam games; keep a note in your credits file that you made them with jsfxr.

Time

Minutes.

Free vs paid

Free, with an optional Pro version.

Common questions

Does it work offline? The website runs in the browser; the original desktop sfxr and similar tools such as Bfxr are alternatives.

Which format should I use in my engine? WAV for short effects is supported by Unity, Godot and Unreal.

Where it fits in the Sefism roadmap

It is a practice pick in the art and audio stage and one of the roadmap's tools. Use it in every jam.