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Stream-copy lossless · Bit-identical output · No watermark

Audio Trimmer

Cut a clip out of an MP3, WAV, M4A, OGG, FLAC, AAC, or OPUS — fast and lossless, no re-encode.

100% freeNo file size limitNo watermarkNo sign-up
  1. 1Pick file
  2. 2Configure
  3. 3Download
Lossless stream-copy: the audio bytes are copied directly from source to output for the trimmed range. No quality loss, near-instant processing. Output format matches input (MP3 in → MP3 out).
  • Files never leave your browser — processed entirely on your device
  • No upload, no queue, no waiting for a worker to free up
  • No file-size cap from us — limit is your device's RAM

About Audio Trimmer

AntiUpload's Audio Trimmer cuts a precise slice out of an audio file — useful for making a ringtone from a song, extracting a podcast clip for quoting, trimming the silence from the start of a voice memo, or pulling a sound effect out of a longer recording. The tool runs FFmpeg's stream-copy mode (`-c copy`) which doesn't decode or re-encode the audio — it copies byte ranges from the source to the output. This means: zero quality loss, near-instant processing (a 30-second cut from a 1-hour podcast takes ~2 seconds), and the output's audio stream is bit-identical to the source's.

The catch with stream-copy: the cut snaps to the nearest keyframe (audio frame boundary) at or before your requested start time — typically 25 ms drift for MP3/AAC frames, 50 ms for OGG. For voice / music content this is imperceptible. The format is preserved end-to-end: MP3 in → MP3 out, WAV in → WAV out, M4A in → M4A out. No format conversion happens; if you want to convert format during trim use our Extract Audio tool instead (which takes video or audio input and outputs to any of the 5 audio formats).

Common use cases: ringtone-making (most phones accept any MP3 up to ~30 seconds), podcast clip-pulling for social sharing or transcription, audiobook chapter trimming, sound-effect extraction from longer recordings. Online competitors (online-mp3-cutter, MP3Cut.net, Audio-Trimmer.com) all cap free uploads at 50-300 MB and ad-cluttered; ours runs locally with no size cap and no ads. The lossless stream-copy approach is also better — most online trimmers re-encode (small but real quality loss) because their server-side pipeline supports re-encode by default.

How it works

  1. Drop your audio fileAccepts MP3, WAV, M4A, OGG, FLAC, AAC, OPUS. No size limit — multi-hour podcasts or audiobooks work fine.
  2. Set start and end times in secondsDecimal seconds OK (12.5 for 12.5 s). Use 90 for 1:30. The trimmed segment is the range [start, end]; everything outside is dropped. Display tooling for waveform / scrubbing is on the roadmap.
  3. Click Trim audioStream-copy is near-instant — a typical trim completes in 1-3 seconds regardless of source length. The audio stream is bit-copied, not re-encoded.
  4. Download the trimmed fileOutput container matches input (MP3 in → MP3 out, WAV in → WAV out, etc.). Output filename appends `.trimmed.<ext>` so you can tell it from the source.

When to use Audio Trimmer

Making a ringtone from a song
Phones accept any MP3 up to ~30 seconds (iPhone 40s, Android varies). Trim the chorus or hook out of a song, drop into the phone's ringtone folder. The lossless trim preserves the source quality exactly.
Pulling a podcast quote for social sharing
Twitter / Bluesky / Mastodon accept short audio uploads. Trim a 30-60-second quote from a longer podcast episode, share with attribution.
Trimming silence from voice memos before sending
iPhone Voice Memos / Android voice recorders often have several seconds of dead air at the start while you start the recording. Trim the silence + the awkward "is it recording?" mumble before forwarding.
Extracting an audiobook chapter to its own file
Audiobooks delivered as single MP3 files can be split into chapters by trimming each section to its own output. Useful for jumping into specific chapters without scrubbing.
Sampling sound effects from longer recordings
Field recordings, ambient sound, or any longer source where you only need a brief segment. Trim once to extract, no quality loss vs source — important for sample-pulling into a music project.

Frequently asked questions

How to trim MP3 online for free without watermark?
Drop your MP3 into AntiUpload Audio Trimmer, set start and end seconds, click Trim. No watermark, no upload, no size cap. The trim is lossless — output audio is bit-identical to the source for the trimmed range. Compare to Audio-Trimmer.com (ad-cluttered, 50 MB cap), online-mp3-cutter.com (limits), MP3Cut.net (paywall above 100 MB).
Will trimming reduce audio quality?
No — we use FFmpeg stream-copy which doesn't decode or re-encode. The output's audio bytes are literally copied from the input for the requested range. Quality is bit-identical to the source. Most online trimmers re-encode (small but real quality loss); ours doesn't.
Best free audio cutter online?
AntiUpload Audio Trimmer — lossless stream-copy, 5 supported formats, no watermark, no signup, no size cap, no upload. Audacity (desktop, free, open-source) is the gold-standard alternative if you want non-browser. Online competitors all upload your file and cap free tier at 50-300 MB.
How precise is the cut?
Stream-copy snaps to the nearest audio frame boundary at or before your requested timestamp. For MP3 / AAC that's ~25 ms drift; for OGG ~50 ms. Imperceptible for voice / music. For sample-accurate cuts (rare — usually only musical-production use cases), use a desktop DAW or Audacity which can decode and trim at sample level.
Can I trim multiple ranges out of one file?
Not yet — V1 trims a single range. Multi-range trim ("keep these 3 segments, drop everything else") is on the roadmap. Workaround: trim each segment separately, then join with our Audio Joiner.
Why is start time before end time validated?
End time must be greater than start, otherwise the trimmed segment is zero or negative duration. We validate before submitting to FFmpeg so the error surfaces immediately as a UI hint rather than as a cryptic FFmpeg error.
Does it work on protected DRM'd audio (Apple Music, Spotify, Audible)?
No. The tool requires unencrypted audio files. DRM'd content from streaming services can't be processed by FFmpeg — that's a deliberate restriction by the platforms, not something this tool can bypass. The tool works on any audio file you own outright (purchased downloads, your own recordings, royalty-free music, etc.).

Related tools

Audio JoinerCombine two or more audio files into one — pick MP3, WAV, M4A, OGG, or FLAC output, with optional crossfades or silence gaps between clipsChange Audio VolumeMake an audio file louder or quieter — multipliers from 0.25× to 3×, output to MP3 / WAV / M4A / OGG / FLACExtract AudioPull the audio track out of any video — choose MP3, WAV, OGG, M4A, or FLAC. Quality presets, mono/stereo, optional VBR for lossy formatsAuto-Cut SilenceRemove dead air from podcasts and videos — silencedetect finds the quiet parts, the rest concats together. Adjustable threshold and padding