Free Online Delay / Echo
Add rhythmic echoes, from slapback to space.
Drag & drop your audio file here
or
Max file size: 100 MB · MP3, WAV, FLAC, OGG
Original
beats per minute
musical key
Time between echoes. Short times (80-150 ms) give slapback; long times give rhythmic echoes.
How much echo feeds back into itself - higher values mean more repeats before fading out.
Loudness of the echoes relative to the original. 0% is fully dry.
Processing…
Result
How it works
Delay is one of the oldest and most musical effects: a copy of your audio plays back a fraction of a second later, then again, then again, each repeat quieter than the last. Short delays (under 150 ms) create slapback thickness; longer ones create rhythmic echoes that can be timed to the tempo of a song.
You control three things: delay time (the gap between repeats, up to 1 second), feedback (how much of each echo feeds back to make more echoes), and mix (how loud the echoes sit against the original). The implementation is a classic feedback delay line rendered per channel, so stereo recordings keep their stereo image.
This is a buffer (offline) tool: the whole file is rendered with your settings and returned as a downloadable file. Everything runs client-side in your browser, so your files never leave your device and nothing is uploaded anywhere.
Frequently asked questions
What is the difference between delay time, feedback and mix?
Delay time sets the gap between echoes (in milliseconds). Feedback controls how many echoes you hear - each repeat feeds back into the delay line and fades a little. Mix sets how loud the echoes are compared to the original dry sound.
What delay time should I use for vocals?
Try the Slapback preset (120 ms) for subtle thickness, or 400-500 ms timed to the song for rhythmic echoes. A handy trick: delay time in ms = 60,000 / BPM gives quarter-note echoes (500 ms at 120 BPM).
Will high feedback cause runaway echoes?
No - feedback is capped at 90%, so echoes always decay instead of building forever. At 90% you get a long, slowly fading tail; at 0% you hear exactly one echo.
Is there a file size limit? Is it private?
Files up to 100MB are supported. The delay is rendered offline entirely in your browser - your audio never leaves your device.