Move from half speed to double speed in 0.05× steps.
RATE / AVAILABLE NOW
Speed & Pitch
Change the energy. Slow down or accelerate a clip with natural linked pitch movement.
RATE / dedicated toolFiles never leave this tab
00:00LOCAL BUFFER--:--
Preview controls appear after you add or generate audio.
GUIDE / change audio speed online
How does changing audio speed affect pitch?
Changing playback speed by resampling makes audio shorter and higher in pitch when accelerated, or longer and lower in pitch when slowed down. SoundTools applies that linked, tape-style change from 0.5× to 2× inside your browser. It does not preserve pitch or adjust pitch independently, and the result exports as WAV.
FIELD NOTES / 01
A deliberate variable-speed effect
At 2× speed, the output contains roughly half as many samples and lasts about half as long. At 0.5× speed, it contains roughly twice as many samples and lasts about twice as long. The control moves in 0.05× steps for quick experimentation.
This tool uses straightforward linear resampling. It is useful when the rising or falling pitch is part of the desired effect, similar to changing tape or turntable speed. It is not time stretching, pitch correction, formant preservation, or an independent pitch shifter.
PROCESS / THREE STEPS
How to speed up or slow down audio
- 01
Load a recording locally
Choose an MP3, WAV, M4A, AAC, or OGG file. The browser decodes it and shows the source duration without sending it anywhere.
- 02
Set a playback rate
Choose a value from 0.5× to 2×. Values below 1× make the result slower and lower; values above 1× make it faster and higher.
- 03
Compare and export
Process the new rate, listen beside the original, and download a WAV when the linked speed and pitch effect fits your project.
SIGNAL NOTES / VERIFIED BEHAVIOR
What this tool actually does
Clear limits are part of a useful tool. These values describe the processor currently running in this page.
Faster becomes higher and shorter; slower becomes lower and longer.
The resampled result is created locally with up to two channels.
USE CASES / 02
When linked speed and pitch is useful
- Tape-stop and tape-speed ideas
Create an obviously slowed or accelerated character for transitions, samples, and experimental edits.
- Fast review copies
Make a shorter, higher-pitched version of spoken material when natural voice quality is not required.
- Sound-design variations
Turn one recording into lower, heavier textures or brighter, faster effects without a full desktop editor.
QUESTIONS / PRACTICAL ANSWERS
Questions about this tool
Answers based on the current browser processor—not promises about a future version.
01Can I change speed without changing pitch?
No. This tool intentionally links speed and pitch. Slower audio becomes lower, and faster audio becomes higher, like variable-speed tape playback.
02What speed range can I use?
The interface supports 0.5× through 2× in 0.05× steps. The output duration changes inversely with the selected rate.
03Can I shift pitch independently?
Not in this version. There is one playback-rate control, so pitch and duration move together rather than as independent parameters.
04Will changing speed preserve stereo?
Yes. Each available channel is resampled using the same rate so left and right remain synchronized.
05Is the audio processed online?
The page is online, but the audio processing is local. Your browser sends the decoded samples to a dedicated worker inside the tab, not to a remote server.