Online Synthesizer – Fluoresynth

You can leave a review here. We also have VST and AU versions for your DAW.

This app may not load or play sound in older web browsers and operating systems. Audio may sound choppy on low-performance devices.

Fluoresynth Online Web Synthesizer

How to play Fluoresynth

There are 3 ways to play notes with Fluoresynth:

    • Click or tap the onscreen keyboard.
    • Play with the bottom two rows of keys on your computer keyboard (z, s, x, d, c, v, g, b, h, n, j, m, etc.)
    • Plug in a MIDI keyboard/device to your computer. MIDI supported in Chrome and Opera.


Make better music faster

Musicians want to spend their time making music, not learning how to use a particular synth.

Fluoresynth allows you to play with a rich soundscape without needing a complicated interface. You’ll immediately start making music instead of figuring out controls.

Place your mouse over the sliders to see how each one changes Fluoresynth’s sound.

It’s easier than deciphering a wall of knobs.


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Precise Harmonics

Fluoresynth produces an audio signal composed of a fundamental tone and 12 overtones. It produces no noise and filters all aliased frequencies.

How does Fluoresynth work?

The Fluoresynth synthesizer uses the harmonic series to create pitched musical tones. This series also determines the sounds of string, brass, and woodwind instruments.

Unlike traditional instruments, you can customize Fluoresynth’s harmonics as you play it.

Fluoresynth’s harmonic series consists of a fundamental tone and 12 overtones. The relationship between the fundamental and its overtones determines the sound’s brightness and warmth.

Mellow or Bright Timbre

Fluoresynth sounds mellower when the overtones are much quieter than the fundamental frequency.

Turning up the overtones’ amplitude brightens Fluoresynth’s timbre.

The Timbre slider controls the overtones’ amplitude.


Warm or Metallic Waveform

The waveform shape determines the distance between each overtone. You can control the waveform shape with the Waveform slider.

Dense overtones produce warmer sounds.

Spaced overtones sound metallic, like bells.


Dynamic Sounds

Changing the timbre or waveform over time can make the sound more interesting. Fluoresynth has several ways of making notes more dynamic.

Two envelopes control the Volume and Timbre amounts over the lifetime of each note.

Four low-frequency oscillators control periodic Volume and Timbre changes, plus Vibrato and Stereo Panorama effects. You can synchronize all four low-frequency oscillators to the tempo of your song.


VSTi/AUi Soft Synth Plugins

VST and AU plug-in files are available for purchase. These files are compatible with the most popular recording software and Digital Audio Workstations. Versions for both Windows and Mac.


Free online synthesizer you can play in your browser

You can play Fluoresynth in your browser right now. Works with a MIDI controller in Chrome or Opera. Works best on desktop.