Add Fade to Audio
Smooth Fade-In and Fade-Out Transitions
Need to use Add Fade to Audio right now?
Fade-in and fade-out durations are set independently, so you can tune each end to taste.
Drop an audio file, or click to browse
Processed locally in your browser — never uploaded
Smooths the start and end of a track instead of an abrupt cut-in or cut-off — a small touch that makes clips sound much more polished.
Features
- Runs entirely in your browser
- Privacy-first — your data is never uploaded
- Real-time, instant results
- 100% free, no sign-up required
- Works on desktop, tablet, and mobile
- No installation needed
Who uses this tool?
About Add Fade to Audio
An audio clip that starts or ends abruptly — cutting in mid-sound or stopping suddenly — sounds noticeably rougher than one with a smooth fade at each end, a small detail that makes a real difference in how polished a clip feels. This tool applies independently adjustable fade-in and fade-out durations to any audio file.
A real FFmpeg build compiled to WebAssembly applies both fades entirely inside your browser using FFmpeg's afade filter, computing the fade-out's start point automatically from the file's detected duration and your chosen fade-out length, so the fade always lands correctly at the very end of the clip regardless of how long the file is.
Fade-in and fade-out durations are set independently, since the right amount of smoothing at the start often differs from what's needed at the end — a quick half-second fade-in with a longer, more gradual fade-out is a common combination for many types of content.
This applies a standard linear-style fade curve (FFmpeg's default), the same fundamental technique used in professional audio editors for basic fade effects — a reliable, widely-understood default rather than an exotic curve shape.
How it works
- Upload your audio file. Duration is detected automatically.
- Set fade-in and fade-out lengths. Adjust each independently, in seconds.
- Apply and download. Smooth transitions at the start and end, re-encoded as MP3.
Examples
Polishing a music clip's start and end
Input
raw clip, 1s fade-in, 3s fade-out
Output
an MP3 with smooth transitions instead of abrupt cuts