Cut, trim and split audio in your browser
Drag the handles on the waveform or type exact times, listen to what you picked, and save. Cuts are made without re-encoding, so the sound quality stays exactly the same.
Runs on your device · 0 bytes uploaded
How to cut & Split Audio
- Add one MP3 or M4A file.
- Choose Trim to keep one part, or Split to cut it into several. Drag the handles or type times like 1:30.5, and press Preview to listen.
- Click “Save audio” and download your file, or all the parts in one ZIP.
Private by design — and you can check
Your files are never uploaded, because there is nowhere to upload them to.
- No upload step existsFiles are read and written inside this browser tab. There is no server that could receive them.
- The browser enforces itThis page’s Content Security Policy only allows connections back to this site, which serves nothing but the app itself.
- See for yourselfOpen developer tools, watch the Network tab and run a job: no request carries your document.
- Open sourceEvery line is on GitHub, built on qpdf, pdf.js & pdf-lib.
Frequently asked questions
Are my files uploaded anywhere?
No. Fizzdoc does the work inside your browser tab, using open-source engines compiled to WebAssembly and JavaScript. Your file is read from your device, processed locally, and the result is saved straight back to your device. You can check this yourself: open your browser’s developer tools, go to the Network tab, and run a job — no request carries your file.
Will cutting lower the sound quality?
No. Fizzdoc cuts between the small blocks the audio is already stored in, so nothing is re-encoded and each part sounds exactly like the original. Cuts land within a few hundredths of a second of the time you choose.
Which audio formats work?
MP3 and M4A (including iPhone voice memos and most music files). WAV, OPUS, WebM and others are planned, and help is welcome on GitHub.
Is Fizzdoc free?
Yes. There is no sign-up, no watermark and no daily limit. Fizzdoc is open source under the Apache-2.0 license.
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