auto-trim silence.

What This Is.

a free, in-browser tool that strips dead air from the beginning and end of an audio file. useful when a recording starts with ten seconds of silence before the mic goes hot, or trails off into nothing after the last word.

it uses ffmpeg's silencedetect filter to find silence below -35 dB lasting at least 0.3 seconds, then trims the file to the first and last moment of actual audio.

Nothing Uploads.

the file you drop stays in your browser's memory. ffmpeg.wasm runs the detection and trim locally — no network request at any point. verify this in your browser's network tab.

How It Works.

1. drop your audio file into the target above (or click to choose).
2. preview the audio with the inline player — confirm you hear the silence you want removed.
3. hit "auto-trim silence." the tool detects silence, trims the file, and gives you back the clean version.
4. preview the result and download.

When To Use This vs. Manual Trim.

auto-trim is for the common case: you know there's dead air at the edges and want it gone without thinking about timestamps. if you need to cut a specific segment from the middle of a file, use the manual trim tool instead.

Limits.

• 1 GB file cap. ffmpeg.wasm runs in browser memory.
• desktop browsers only. chrome, edge, firefox, safari, arc — all current versions.
• edges only. this tool trims leading and trailing silence. it doesn't remove silence from the middle of a recording — use the voice activity detection tool to find those gaps.