Set the kept range before export
Start and end controls use the measured source duration. The selected range is decoded for accurate time boundaries, and an optional short fade can soften a hard edit without changing the original source.
Local audio cutter
Cut or trim an audio file
Choose one file and the time range to keep. The local worker decodes that range, can apply short click-prevention fades, and creates a separately named MP3 or WAV result.
Your selected file stays on this device. No upload, account, or server-side media job.
Browser-local workspace
Choose a local source to begin.
Choose one local audio file—or a local video on the conversion route—then create a separate, verified MP3 or WAV result. The source is not sent to Aftermath, modified, or handed to a fallback service.
No upload, account, or server-side media job.
The local workspace loads after you choose a source.
Create a compatible local result
Trimming uses local decode and re-encode so exact boundaries and fades behave consistently. Choose MP3 for a smaller, broadly compatible result or WAV for uncompressed 16-bit PCM output.
Private browser handling
Your source remains under your control.
Aftermath reads, decodes, processes, encodes, and verifies the selected file in this browser. It preserves the source and offers a separate MP3 or WAV result; unsupported inputs are never sent to an upload fallback.
Try a measured example
Keep 1.5 seconds of a three-second sound
The source is a synthetic tone. We kept the first 1.5 seconds as WAV, then sent that result straight to compression.
- Choose an audio file and set the part to keep.
- Create and preview the trimmed copy.
- Choose Make it smaller to continue with that copy.
| Original tone · WAV | Bytes: 264,644 Seconds: 3 |
|---|---|
| Trimmed tone · WAV | Bytes: 132,344 Seconds: 1.5 |
The WAV result measures 1.5 seconds. MP3 timing can include a little encoding padding; compare the downloaded result when duration limits matter.
Tested: · Chromium 149.0.7827.55
How we checked
These files passed through the actual tool controls. Downloads were reopened to check sizes, duration, dimensions, or page structure. Capture used synthetic streams; hardware permissions were not tested.
These synthetic samples are free to reuse under CC0. No personal files or recordings were used. Your results may differ.
How to use this tool
Use Audio Cutter when you need to keep one exact start-to-end range from an existing local audio file. The workspace reads the measured duration, lets you mark the retained section, optionally applies short click-prevention fades, then decodes and re-encodes only that range as MP3 or 16-bit PCM WAV. It does not preserve the full track merely to change format; that separate intent belongs to Audio Converter.
What to choose and what you get
What to choose
- one selected local audio file
Result
- a separately downloaded MP3 or 16-bit PCM WAV result
Supported use
- One readable local audio file with a measurable duration and a deliberate start and end boundary.
- Optional short linear fades at the retained range edges to reduce clicks from hard cuts.
- A separately named MP3 or 16-bit PCM WAV result that is reopened and measured before download.
Before you start
- Video input, multiple-file joins, overlapping clips, transitions, or a multitrack editing timeline.
- Automatic pause detection, whole-track loudness processing, or format-only conversion as the route’s task.
Supported formats
- Accepted formats: MP3, WAV, M4A, AAC, Ogg, Opus, FLAC.
- Output formats: MP3, WAV.
Browser support and permissions
- Modern browser with JavaScript and support for the selected audio container and codec; memory and performance vary by device.
- No camera, microphone, or screen permission is needed.
Choose the right settings
- Use Audio Cutter when you choose one contiguous portion to retain.
- Use /convert-audio when the complete primary track should remain and only MP3/WAV representation changes.
- Use /remove-silence when low-level runs throughout the recording should be shortened automatically, or /audio-tools when undecided.
- Listen to the separately reopened cut before replacing the source.
Worked example
A five-minute recording should keep 01:10–02:05 and export that interval as MP3.
Starting facts
- The selected audio has a readable primary track.
- The keep range is explicit and within the decoded duration.
Observed operation: Set the start and end times, choose MP3 and create a separate local result containing the selected range.
Review the result: Listen at both cut boundaries and compare the output duration and channel behavior with the intended selection.
Boundary: Cutting can re-encode audio and does not remove noise, normalize loudness or preserve unsupported metadata and tracks.
What you can do
Keep one user-selected time range from a local audio file and export that cut as MP3 or WAV
Choose another tool when
- Full-duration MP3 or WAV format conversion belongs to /convert-audio.
- Automatic shortening of quiet runs throughout a recording belongs to /remove-silence.
- This route does not splice multiple clips, edit a multitrack timeline, or accept a video source.
If it does not work
- A source with no decodable primary audio track or readable duration cannot provide a valid cut range.
- An empty, reversed, or out-of-bounds start and end selection is rejected before encoding.
- The download is withheld when local decoding, MP3 or WAV encoding, bounded output, or reopened-result validation fails.
Things to know
- Codec support, performance, and memory use vary by browser, device, source, and operation.
Privacy boundary
The selected audio stays in the current browser session and is not sent to an Aftermath processing service. How local processing is verified.
What this tool verifies
Checks the displayed limits and reports or creates a separately downloaded MP3 or 16-bit PCM WAV result from one selected local audio file.
Check before sharing
Full-duration MP3 or WAV format conversion belongs to /convert-audio.