Edit an audio file in the browser
Use this single-track editor to reverse audio, change Tempo / speed, shift Pitch shift, and add fades. Processing happens in the browser, and the tool's script makes no upload request.
Load a file and select the part to edit
Click browse files or drop files into the upload area. The waveform lets you click to seek or drag to select a range. Leave Apply to entire file selected for a full-file edit, or choose Apply to selected range.
When a range is selected, effects run inside it. Samples outside the range are copied through before any uniform safety-gain adjustment; the result is still a newly encoded WAV. A speed change can alter the edited region's length and therefore the total duration. Pitch shift is designed to preserve the edited region's duration.
Choose effects and review the controls
- Turn on Reverse to reverse the selected scope.
- Set Tempo / speed from 25% to 400%. With Preserve pitch on, the control shows a WSOLA time-stretching note. With it off, linear resampling changes pitch with speed.
- Set Pitch shift from ±12 semitones. The control displays an algorithm note, and the duration is preserved by the pitch-shift operation.
- Set Fade in (seconds) or Fade out (seconds), then choose Fade curve: Linear, Exponential (ease-in), or Logarithmic (ease-out).
Apply, check warnings, and listen to the result
Choose the bit depth and review the automatically updated Duration & format changes, then use the Original and Edited A/B buttons to compare the result.
Warnings may flag artifacts at extreme speed or pitch settings, including warbling, smeared transients, or unnatural-sounding voices. The tool can also reduce output gain uniformly when the processed signal exceeds the safety threshold. A full-scale warning means the source may already contain full-scale or near-full-scale samples; it does not prove that the source was clipped.
Process multiple files
Click Add more files to extend the queue. The current effect settings are applied automatically to each queued file. Each queued file has its own waveform selection. If Apply to selected range is enabled for a file without a selection, that file uses the whole file and shows a warning. Use Download all (ZIP) after processing.
Download the edited audio
Choose 16-bit PCM, 24-bit PCM, or 32-bit float under Bit depth, then click Download edited file. The tool creates a new WAV at the source sample rate. It is not a byte-for-byte copy of the source file.
How to use the Audio Effects Editor
- Click browse files or drop one or more files into the upload area.
- Drag on the waveform if you want to edit a range, then choose Apply to selected range.
- Set the effects, fade options, and Bit depth.
- Review the automatically updated summary and warnings, and compare Original with Edited.
- Click Download edited file. For a queue, use Download all (ZIP) after every queued file has been processed automatically.
Limitations to know before processing
The browser must be able to decode the input through AudioContext.decodeAudioData. The page shows common audio extensions, but the implementation does not define a universal supported-format list. If decoding fails, the file is not added and the page shows a visible error with the affected filename so you can choose another supported audio file or try again.
There are no documented file-size, duration, memory, or processing-time limits. Large files may need more browser memory and time. Extreme settings can create audible artifacts, and the warning logic states that no formant correction is applied to large pitch shifts.
Processing is local to the browser, and this tool's script makes no upload request. The local implementation does not establish account policy or usage limits.
What this tool does not do
This is a single-track timeline effects editor, not a multi-clip editor or a loudness/noise tool. It does not join multiple files together or crossfade between them - use Merge Audio for that. It does not change overall loudness or apply gain/compression to match a target level - use Volume Normalizer. It does not remove hum, hiss, or room echo - use Audio Cleaner.
Frequently asked questions
Does changing tempo always keep the pitch the same?
Only when you turn on Preserve pitch. With it on, the Tempo / speed control shows a WSOLA time-stretching note and aims to keep pitch constant. With it off, the tool uses simple linear resampling, which changes pitch and duration together, like speeding up or slowing down a tape.
Can I apply an effect to only part of the file?
Yes. Drag a region on the waveform to select a range, choose Apply to selected range, and every enabled effect runs inside that region. Samples outside the region are copied through before any uniform safety-gain adjustment, and the result is exported as a newly encoded WAV.
Does this tool join clips or change loudness?
No. This is a single-track timeline editor. Joining multiple files together and crossfading between them lives in Merge Audio; overall loudness/volume changes live in Volume Normalizer; noise/hum/hiss cleanup lives in Audio Cleaner.
Why did the file's duration change after I changed speed or pitch?
A speed/tempo change directly changes how long the edited region plays back. A pitch-only shift is designed to keep duration the same - if you also change speed, the two effects combine and the duration/format panel shows the resulting before/after duration.