Audio Trimmer & MP3 Cutter
Cut audio down to just the part you want, or make a phone ringtone with a smooth fade in and out. Fast lossless trim by default. No upload, works offline — your audio stays on your device.
Runs entirely in your browser — your audio is never uploaded.
- No upload Your video never leaves your device — it is processed locally.
- Works offline After the first load it runs with no internet connection.
- No size or daily limits No file caps, no paywalls — only your device memory.
- Private & safe Skip sketchy upload sites; nothing is sent to a server.
How it works
Trimming is handled by ffmpeg compiled to WebAssembly and run inside your
browser. In the default fast mode it uses -ss and -to with
-c copy, which copies the selected span of audio without decoding it — instant and
lossless, snapping to the nearest frame boundary. In ringtone mode it re-encodes the trimmed
section to AAC and applies an afade filter for a one-second fade in and a
two-second fade out, then writes a .m4a file. Either way the work happens on your
device, so your audio is never uploaded. The first run downloads the engine once (about 9 MB),
then caches it for offline use.
How to trim audio or make a ringtone
- Choose an audio file with the drop zone above, or drag one onto it.
- Enter the start and end times in seconds or HH:MM:SS.
- Leave it on the fast lossless trim, or tick Ringtone for a faded .m4a.
- Press Trim audio, then click Download when it finishes.
Fast trimming is near-instant because the audio is copied, not re-encoded. Ringtone mode re-encodes a short section, which is still quick. For a phone ringtone, keep the clip to roughly 30–40 seconds.
Why trim audio locally instead of on an upload site
Online MP3 cutters upload your file to a server before they can trim it, which is slower, hands your audio to a third party, and sometimes adds limits or watermark-style branding. Cutting in your browser removes the upload step, keeps the audio private, and is lossless in the default mode. It also avoids the safety concerns around free file sites — in March 2025 the FBI warned that some free online converter sites were being used to spread malware, so keeping the work on your own machine is the safer choice.
| Local (this site) | Typical cloud tool | |
|---|---|---|
| Upload required | No | Usually |
| File-size caps | None (device memory) | Common |
| Works offline | Yes, after first load | No |
| Files stay private | Yes — never sent | Sent to a server |
Common uses
Making a custom ringtone or text-tone from your favourite song, cutting a sample or loop out of a track, trimming silence or chatter from the start of a recording, shortening a podcast clip to share, or grabbing a single chorus. The fast mode is ideal for quick, lossless edits, while ringtone mode gives you a polished, phone-ready file in one step.
More video & audio tools
Frequently asked questions
How do I make a ringtone for my phone?
Load your song, set the start and end of the part you want (keep it under about 30–40 seconds, since that is what most phones use), and tick "Ringtone". The tool exports a faded .m4a, which is the format iPhones use for ringtones via your computer, and which Android also accepts. Transfer the file to your phone and set it as your ringtone in the sound settings.
Why does the fast trim keep the original quality?
The default trim uses stream copy (-c copy), which slices out the selected span of audio without decoding or re-encoding it. That makes the cut nearly instant and completely lossless — the kept audio is bit-for-bit identical to the source. The trade-off is that a copy can only cut at the audio frame boundaries, so the start or end can land a fraction of a second from your exact time.
What does the ringtone option change?
Ringtone mode re-encodes the trimmed section to AAC in an .m4a file and adds a one-second fade in at the start and a two-second fade out at the end, so the tone begins and ends smoothly instead of cutting off abruptly. Because it re-encodes, it is slightly slower than the lossless trim and involves a small, usually inaudible quality change.
Is my audio uploaded to trim it?
No. Everything runs locally with ffmpeg compiled to WebAssembly. Your file is read into the browser, trimmed on your device, and the result is written there for download. Nothing is sent to a server and no copy is stored online.
What time format should I enter?
You can use seconds (for example 30) or HH:MM:SS (for example 00:00:30). The start is where the kept clip begins and the end is where it stops, both measured from the beginning of the original audio. For a ringtone, the fade timings are calculated from the length you select.
Does it work offline?
Yes. The site is a Progressive Web App, so it works without a connection after the first visit, and the ffmpeg engine is cached after its one-time download so trimming keeps working offline.
All processing happens on Video Tools entirely within your browser. Audio is never uploaded to a server.