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Rhad ac am ddim Video Speed Changer

Speed up or slow down a video from 0.25× to 4×, with pitch-corrected audio. Great for slow-motion and timelapse. Runs entirely in your browser.

Dim cyfyngiad maint ffeilMae ffeiliau'n aros yn breifatNid oes angen mewngofnodiAm ddim am byth

Gollwng ffeiliau yma, neu cliciwch i bori

MP4, WebM, MOV, AVI, Video dim cyfyngiad maint ffeil

Pori ffeiliau

Nid yw eich ffeiliau byth yn gadael eich dyfais. Mae'r holl brosesu yn digwydd yn lleol yn eich porwr.

Speed up or slow down a video (0.25×–4×), with pitch-corrected audio. Runs entirely in your browser.

Optimize for your platform

Make a Slow-Motion Video Speed Up a Video / Timelapse Speed Up a Tutorial or Lecture Speed-Ramp a Clip for Social Slow a Video Down to Analyse It

Sut Mae'n Gweithio

Speeding up or slowing down a video means re-timing both the picture and the sound. This does it with FFmpeg in your browser, keeping the audio pitch natural.

1
FFmpeg.wasm loads once
The WebAssembly build of FFmpeg (~30 MB) downloads on first use and is cached afterwards.
2
You pick a speed
From 0.25× (slow motion) to 4× (fast forward / timelapse feel). Your file stays in the browser.
3
Video and audio are re-timed
The video uses setpts to change frame timing; audio uses chained atempo filters that stretch time without altering pitch, so voices stay natural.
4
You download the result
The re-timed MP4 is offered for download and previewed in-page.