PDFCure
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Speed Up or Slow Down a Video, Free

Speed up or slow down a video, 0.25× to 4× — in your browser.

Most tools run entirely on your device

Select a video file

Speed up or slow down a video — 0.25× to 4×. Runs in your browser.

Click to choose, or drop a file here

You can also paste (Ctrl+V / Cmd+V)

Most tools run entirely on your device

About changing video speed

Speeding a video up turns a long clip into a quick highlight or a timelapse; slowing it down gives you a rough slow-motion effect or makes a fast demo followable. This tool does both — 0.25× to 4× — entirely in your browser.

It works by setting the video's playback rate and re-recording it off a canvas, so the picture is resampled cleanly and the file comes out as a normal MP4 or WebM. "Keep audio pitch" is on by default — the browser time-stretches the sound so a voice stays natural at 1.5× or 0.75×. Untick it for the pitch-shift effect (sped-up voice sounds high), or tick "Mute the audio" to drop the sound entirely.

Processing time tracks the output length, not the input: a clip slowed to 0.5× takes twice as long to produce, one sped to 2× takes half. True pitch-preserving slow-motion with motion interpolation (new in-between frames) needs a dedicated video editor; this is the fast, in-browser version.

Supported files

Accepts any video your browser can play. Produces an MP4 or WebM at the new speed.

Is my file uploaded?

No. The speed change is re-recorded from a canvas entirely in your browser — nothing is uploaded.

Common problems

The audio sounds high-pitched or squeaky
Turn on "Keep audio pitch" — that time-stretches the sound instead of resampling it. Or tick "Mute the audio".
Slow-motion looks choppy
This doesn't create new in-between frames. Real slow-mo needs footage shot at a high frame rate.

How to Change Video Speed

  1. 1

    Add your video

    Drop in the clip you want faster or slower.

  2. 2

    Set the speed

    Drag the slider from 0.25× to 4×. 'Keep audio pitch' is on by default; untick it for the pitch-shift effect or mute the audio entirely.

  3. 3

    Apply and download

    Click Change speed; the video is re-recorded at the new rate.

Change Video Speed — frequently asked questions

Does the audio pitch change?+

Not by default — 'Keep audio pitch' is on, so a voice stays natural at 1.5× or 0.5×. Untick it for the pitch-shift effect, or tick 'Mute the audio' to drop the sound entirely.

Is my video uploaded?+

No. It's re-recorded from a canvas in your browser.

How fast/slow can it go?+

0.25× (quarter speed) to 4× (four times). The processing time scales with the output length.

What format do I get?+

MP4 where WebCodecs can re-encode to it, otherwise WebM — whichever your browser supports.

Do you upload my files to a server?+

No — every tool here processes your files entirely on your device, and nothing is uploaded to a server. The only exception is the AI tools, which send the extracted text (not the file) to Claude to do their work.

Is there a file size limit?+

There's no artificial limit we impose, but since processing happens in your browser, very large files (500+ MB or 1,000+ pages) are limited by your device's memory rather than by us.