Audio Trimmer

What it does

Drop an audio file (MP3, WAV, M4A, OGG, FLAC, or anything else your browser can decode), see the waveform, drag the start and end handles to mark the section you want to keep, and export a trimmed WAV. Useful for shaving intros and outros off podcast clips before sharing, cutting a 30-second sample out of a song for a video soundtrack, removing dead silence at the start of a voice note, extracting a quote from a long interview recording, or preparing audio fixtures for a podcast editor (each clean intro / sting / sound effect as its own file).

The waveform display lets you see exactly where speech, music, or silence sit in the file — drag the handles right up against a word boundary, click to play just the selection, and verify before exporting. Output is 16-bit PCM WAV at the source sample rate, which is universally supported (every audio editor, every podcast platform, every video editor accepts WAV input).

Trim is sample-accurate: the cut points are exact to the millisecond level (versus codec-block alignment in formats like MP3 where fades can creep in at frame boundaries). The whole pipeline runs locally via the Web Audio API — no upload, no server, file stays in browser memory.

How to use it

1. Drop your audio file (drag-drop or click to browse). The waveform renders below — typically takes 1-2 seconds for a 5-minute file.
2. Drag the left handle to set the trim start, right handle to set the trim end. Click anywhere on the waveform to scrub the playback head.
3. Click Play to hear just the selected range. Adjust handles by single pixels (= a few milliseconds) for tight trims.
4. Click Export. The selection is sliced from the underlying AudioBuffer and re-encoded as 16-bit PCM WAV.
5. Click Download to save the WAV file. To convert to MP3 afterward, use the audio-format-converter tool or any audio editor.

When to use this tool

• Cutting a clean intro or outro off a podcast clip before sharing.
• Extracting a 30-second song sample for use as background music in a short video.
• Removing dead silence at the start or end of a voice memo.
• Splitting a long interview into individual question/answer clips for transcription or quoting.

When not to use it

• Multi-cut editing (remove the middle, keep start + end) — this is single-range trim. Use Audacity or a DAW for multi-cut.
• Adding fades, EQ, compression, or other effects — that's editing. Use Audacity, Reaper, GarageBand, or a real DAW.
• Long audio files (>30 minutes) — the waveform renders slowly and browser memory becomes a bottleneck around an hour.
• Lossless preservation of MP3 source — output is WAV, which is uncompressed; the source is decompressed once. There's no MP3-to-MP3 lossless trim in the browser (use ffmpeg locally with `-c copy` for that).

Common use cases

• Onboarding a colleague who needs the same calculation/conversion
• Verifying a number or output before passing it on
• Quick use during a typical workday
• Pre-decision sanity-check on inputs and outputs