MP3 Editor
Trim · Volume · Fade Browser-OnlyTrim audio clips, adjust volume, and add fade in/out effects — real-time preview, export as MP3. No uploads, no server.
Drop MP3 file here Release to upload
or click to browse
MP3
WAV
OGG
AAC
Max 100 MB
Your audio file is processed entirely in your browser — it is never uploaded to any server.
Waveform
/
Trim / Cut
Selection:
Volume
0%100%200%
Fade In
Fade Out
MP3 ready to download
Duration: · Size:
Category
🔧 media file converterHow to Use
- Upload an MP3, WAV, OGG, or AAC file
- Drag the purple handles to set trim range
- Adjust volume (0–200%) and fades
- Click Preview Edited to listen
- Click Process & Download to save MP3
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About This Tool
This MP3 editor handles the three edits most audio files actually need. Load an MP3, WAV, OGG or AAC file of up to 100 MB and it draws a waveform you can work against. Drag the trim handles or type exact start and end times to cut the section you want, set a volume level, and add a fade in and a fade out so the clip does not begin or end abruptly. You can play only the trimmed range, loop it while you adjust the settings, and stop at any point, so the edit is checked by ear before you commit. When you are happy, the edited audio is rendered and encoded as an MP3 you can download. Everything is processed inside the browser using the Web Audio API, so the file is never uploaded to a server.
Frequently Asked Questions
No. The file is decoded and processed in your browser using the Web Audio API, and the MP3 is encoded in the page as well. Nothing is sent to a server at any stage, which matters for interview recordings, voice notes and unreleased material you would rather not transmit.
MP3, WAV, OGG and AAC files up to 100 MB. Decoding relies on the browser's own audio support, so an unusual variant may occasionally fail to load. The export is always an MP3, regardless of which of those formats you started with.
It is encoded at 128 kbps, which works out at roughly 15.6 KB per second of audio, or about 1 MB per minute. That is a common setting for speech and general listening. Because MP3 is lossy, avoid repeatedly re-exporting the same file if you care about fine detail.
The maximum fade length is limited by the length of your trimmed selection, since a fade cannot run longer than the audio it applies to. In practice one to three seconds suits music, while shorter fades of a few tenths of a second are usually better for speech so words are not swallowed.
Yes. You can play just the trimmed range, loop it while you adjust the volume and fade settings, and stop at any point. Checking by ear is the reliable way to find a clean cut, because a boundary that looks right on the waveform can still land mid-word or mid-beat.
Decoding, rendering offline and encoding to MP3
Loading a file decodes it into raw audio samples held in memory, and the panel reports its duration and sample rate. The waveform you see is drawn from those samples, which is why the picture matches the sound precisely rather than being an approximation.
Your edits are applied in an offline rendering pass rather than in real time. The trim simply selects the span of samples between the start and end points. Volume is a gain multiplier: 100 per cent leaves the samples unchanged, 50 per cent halves their amplitude, and values above 100 per cent scale them up. The fades apply a ramp to that gain, rising from silence to full level across the fade-in duration and falling back across the fade-out, with the maximum fade length limited by the length of your selection.
The rendered result is then encoded to MP3 in the page by the lamejs encoder at 128 kbps, at the same sample rate as the source, producing the file you download.
Your edits are applied in an offline rendering pass rather than in real time. The trim simply selects the span of samples between the start and end points. Volume is a gain multiplier: 100 per cent leaves the samples unchanged, 50 per cent halves their amplitude, and values above 100 per cent scale them up. The fades apply a ramp to that gain, rising from silence to full level across the fade-in duration and falling back across the fade-out, with the maximum fade length limited by the length of your selection.
The rendered result is then encoded to MP3 in the page by the lamejs encoder at 128 kbps, at the same sample rate as the source, producing the file you download.
Cutting a 45 second clip from a four minute track
Take a track lasting 4 minutes 12 seconds, or 252 seconds. You want the passage from 0:45 to 1:30, so set the start time to 45 seconds and the end to 90 seconds. The selection is 90 minus 45, which is 45 seconds, just under 18 per cent of the original.
Add a fade in of 2 seconds and a fade out of 3 seconds. The clip now rises from silence across its first 2 seconds, plays at your chosen level for 40 seconds, and falls away across the final 3 seconds. Leave the volume at 100 per cent unless the source is quiet.
Now the output size. At 128 kbps the encoder writes 128000 bits each second, which is 16000 bytes, or roughly 15.6 KB per second. Multiply by 45 seconds and the MP3 comes to about 720 KB before the small overhead of frame headers and tags. The same 45 seconds exported as uncompressed stereo WAV at 44.1 kHz would run to roughly 7.9 MB.
Add a fade in of 2 seconds and a fade out of 3 seconds. The clip now rises from silence across its first 2 seconds, plays at your chosen level for 40 seconds, and falls away across the final 3 seconds. Leave the volume at 100 per cent unless the source is quiet.
Now the output size. At 128 kbps the encoder writes 128000 bits each second, which is 16000 bytes, or roughly 15.6 KB per second. Multiply by 45 seconds and the MP3 comes to about 720 KB before the small overhead of frame headers and tags. The same 45 seconds exported as uncompressed stereo WAV at 44.1 kHz would run to roughly 7.9 MB.
Quality, re-encoding and practical limits
Every MP3 export here is re-encoded at 128 kbps, which is a reasonable general-purpose setting for speech, podcasts and background music. It is a lossy format, so exporting a file that was already an MP3 means compressing audio that has been compressed once before, and a little detail is lost each time. Where quality matters most, start from the highest quality source you have rather than from a file that has been through several rounds.
Use the preview and loop controls before exporting. Judging a fade by the numbers is unreliable; two seconds sounds gentle on a sustained note and abrupt on a spoken sentence that starts mid-word. Listening to the trimmed range on loop is the quickest way to find a clean cut point, ideally at a natural pause.
Two practical limits. Decoding holds the whole file in memory, so very long recordings can be slow on a modest phone, and the 100 MB ceiling exists for that reason. And pushing the volume well above 100 per cent can clip loud passages into distortion that cannot be undone afterwards.
Use the preview and loop controls before exporting. Judging a fade by the numbers is unreliable; two seconds sounds gentle on a sustained note and abrupt on a spoken sentence that starts mid-word. Listening to the trimmed range on loop is the quickest way to find a clean cut point, ideally at a natural pause.
Two practical limits. Decoding holds the whole file in memory, so very long recordings can be slow on a modest phone, and the 100 MB ceiling exists for that reason. And pushing the volume well above 100 per cent can clip loud passages into distortion that cannot be undone afterwards.