Audio speed changer
Play a lecture, podcast or interview faster without the chipmunk voice, and see how much time each speed actually saves you. The file stays on your device - nothing is uploaded.
What each speed costs you in time
| Speed | Takes | Saves |
|---|
Pitch correction is on, so voices stay at their normal pitch at every speed. Arrow keys work too: left and right skip 10 seconds, up and down change the speed.
Read it in ten minutes instead - transcribe the file →Two hours at 1.75x is still an hour and eight minutes
Speeding audio up feels like a productivity win until you do the arithmetic. A two-hour lecture at 1.75x still takes one hour and eight minutes of sitting there paying attention, and you cannot search it, quote it, or skim back to the bit about the exam. The table above is there to make that trade honest: pick a speed and see exactly what it buys you.
The alternative is not listening faster but reading instead. A transcript of the same two hours takes a few minutes to produce and about ten to skim, with timestamps to jump back to anything worth hearing in the speaker's own voice - the first 15 minutes are free. Turning a lecture recording into study notes walks through the whole workflow. If what you have is a video file, pull the audio out of it first.
Audio speed changer - FAQ
Is my file uploaded?
No. The file is played by your browser straight from your device. Nothing is sent anywhere, and the tool works offline once the page has loaded.
Why do voices not sound squeaky at 2x?
Browsers separate speed from pitch, so playing faster does not raise the frequency the way speeding up a tape did. Every current browser does this by default for audio, and this page asks for it explicitly.
Can I download the sped-up file?
No, and no tool that runs purely in a browser tab can honestly offer that. Changing the speed of a file without wrecking the pitch means re-encoding it with time-stretching, which is a heavy piece of processing rather than a playback setting. This page changes how the file plays, not what the file is.
What speed is actually usable?
For a clear single speaker, most people settle at 1.5x to 1.75x within a few minutes. Overlapping speakers, a strong accent, or unfamiliar technical material all pull that number down. Above 2x comprehension falls off for almost everyone, whatever the internet says.
Does it remember where I stopped?
Yes. Your position is saved in this browser against the file name and size, so reopening the same lecture picks up where you left off. It never leaves your device.
Can I use a video file?
Yes - drop in an MP4 or MOV and it plays the soundtrack. If you want the audio as its own file, use the extract audio tool.
Which file types work?
Whatever your browser can play: MP3, M4A, AAC, WAV, OGG and FLAC are safe on desktop, along with MP4 and MOV video. A file your browser refuses to play here would not play in a normal player either.