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Change Video Speed

Speed up or slow down an MP4, MOV, or WebM and download the new clip, right in your browser.

Video
Drop a video here or click to browse
or paste from clipboard (Ctrl+V) · MP4, MOV, WebM, MKV
Files stay in your browser. Nothing is uploaded.
Speed

How to change the speed of a video online

  1. Add your video

    Drop in the clip you want to speed up or slow down, or click to browse. MP4, MOV, WebM, MKV, and AVI files are accepted.

  2. Choose a speed

    Pick 0.25x or 0.5x for slow motion, or 1.5x, 2x, or 4x to move faster. Changing the setting clears any previous result.

  3. Change speed

    Click Change speed. The picture is re-timed and the audio tempo is adjusted to match, so the pitch stays natural.

  4. Download

    The result card lists the chosen speed plus the original and new length. Click Download to save the MP4.

Why use this tool

Five speed presets

0.25x and 0.5x stretch a clip into slow motion; 1.5x, 2x, and 4x shorten it for faster viewing.

Audio keeps its pitch

The soundtrack has its tempo changed rather than simply being resampled, so voices at 2x stay natural instead of turning squeaky.

Picture and sound stay in sync

The picture and the audio are re-timed by the same factor in a single pass, so nothing drifts.

Silent videos just work

If the file has no audio track, the tool notices and retries with a video-only pass, so screen recordings and animations need no special handling.

Before-and-after durations

The result card shows the original length next to the new one, so you can confirm the change before saving.

Nothing is uploaded

The re-timing runs entirely in your browser, so the clip never leaves your device.

About this tool

This tool changes the playback speed of a video and writes a new MP4. It runs entirely in your browser and re-times the picture and sound together in one pass: the frames are re-timed while the soundtrack has its tempo changed without shifting pitch. Every speed, including 4x, keeps voices at their natural pitch.

Five multipliers are available: 0.25x and 0.5x for slow motion, and 1.5x, 2x, and 4x for getting through footage quickly. Typical uses are doubling the pace of a screen recording or tutorial, slowing a sports or technique clip to study the movement, and tightening a long demo before sharing it. The change requires a re-encode, so a short clip takes seconds while a long video takes minutes, and a desktop browser handles big files more comfortably than a phone. Silent videos work too: when no audio track exists, the tool falls back to a video-only pass on its own.

Processing is local, so the recording never leaves your machine. To speed up only a section, cut it out first and re-time the clip separately. A sped-up file that is still too heavy can go through the video compressor, and a slowed-down highlight makes a good animated GIF.

Frequently asked questions

How do I change the speed of a video?
Drop a video onto the tool or click to browse, choose a speed (0.25x, 0.5x, 1.5x, 2x, or 4x), then click Change speed. The tool re-times the video and audio together and shows you the chosen speed along with the original and new length. Click Download to save the new MP4.
Does changing the speed keep the audio in sync, and does it change the pitch?
Yes, the audio stays in sync with the video. The tool changes the tempo of the audio in a way that preserves pitch, instead of making fast audio sound high or slow audio sound low. So a 2x clip plays twice as fast while voices and music keep their natural tone, and a 0.5x clip slows down without dropping in pitch.
Will speeding up or slowing down reduce the quality of my video?
Changing the speed re-encodes the video, so there is some quality loss, but for everyday footage it is hard to notice. Slowing a clip down does not add new frames, so very slow speeds can look slightly less smooth than the original, while speeding up simply skips frames and stays sharp. The output is a standard H.264 MP4 that plays everywhere.
Which video formats are supported?
You can drop in MP4, MOV, WebM, MKV, AVI, and most other common video files, including silent videos with no audio track. The output is always an MP4 with H.264 video and, when present, AAC audio, which plays on virtually every device, browser, and editor.
Does it work on videos with no sound?
Yes. If a video has no audio track, the tool automatically falls back to changing only the video speed, so silent clips, screen recordings, and animations all work without any extra steps.
Is my video uploaded to a server?
No. The entire speed change runs locally in your browser. Your video never leaves your device, is never uploaded, and is not stored or logged anywhere. The first time you use the tool, it downloads the video engine once, then keeps it ready for the rest of your session.

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