Fade Audio In & Out
Processing entirely on your device — large files may take a moment.
Choose the fade length and the tool probes the file's real duration first, so the fade-out always finishes exactly at the end — the classic fix for tracks that stop abruptly, playlist transitions and ringtone endings.
The afade filter applies a smooth curve to the samples themselves — no re-encoding of anything else, and the output keeps your input format.
How to fade audio
- 1
Select your files
Drag & drop your MP3 files onto the area above, or click to browse. You can add multiple files at once for batch conversion.
- 2
Convert instantly
Click "Convert to MP3". The conversion runs entirely inside your browser using WebAssembly — no upload, no queue, no waiting.
- 3
Download results
Download each converted MP3 file individually, or grab everything at once as a ZIP archive.
About the MP3 format
MP3 (MPEG-1 Audio Layer III) defined digital music: standardized in 1993, popularized by Napster and the first portable players, and freed of all patents in 2017. It is lossy psychoacoustic compression — it discards frequencies the ear supposedly won't miss — at bitrates from 128 to 320 kbps, with ID3 tags carrying title, artist and cover art.
Twenty years of competitors have failed to displace it, because playback support is absolute: every device that has ever played music plays MP3. At 320 kbps even critical listeners struggle to identify it in blind tests, though modern codecs reach the same quality at noticeably lower bitrates.
+Strengths
- ✓Plays on absolutely everything
- ✓Rich tag ecosystem (ID3, cover art)
- ✓320 kbps is transparent for most listeners
!Limitations
- −Lossy ceiling — never a mastering format
- −Less efficient than AAC/Opus at equal quality
- −Low-bitrate artifacts are audible and permanent
Frequently asked questions
Which length should I pick?
0.5 s for tight transitions, 1 s universal, 2-3 s for ambient or cinematic endings. Very long fades on short clips feel like the audio never starts.
Can I fade only one side?
This page applies both. For a single-sided fade, fade the file and trim the unwanted end afterwards (trim is stream-copy and lossless).
Does it work on any format?
Every audio container the converters accept — MP3, WAV, M4A, FLAC, OGG, OPUS and 15 more. Output keeps the input format.