Change video speed.
Slow-mo to hyper-lapse.
Speed up or slow down any video — with audio that keeps its natural pitch. Everything runs in your browser, so nothing is uploaded.
- 0.25× – 8×
- Natural-pitch audio
- No watermark
- Never uploaded
Speed
Drag, or tap a preset2×
Fast-forward
Example: 1 min clip
1:00 → 0:30
Audio
Audio stays clear and natural at this speed.
Which speed should
you pick?
A quick guide to the sweet spots, so your video looks and sounds right.
0.25×–0.5×
Slow motion
Sports, splashes, dance moves and product reveals. Shoot at 60 fps or more for the smoothest result.
0.75×
Gentle slow-down
Tutorials and voice-overs that need a little breathing room, with clear natural audio.
1.25×–2×
Watch faster
Lectures, interviews and screen recordings. Audio stays crisp and natural.
4×–8×
Time-lapse
Sunsets, builds, travel and cleanups. Mute the audio — speech is too fast to follow at this pace.
Good to know
- Slow motion stretches the frames you already have — it doesn't invent new ones.
- Speeding up drops frames as needed so the result never exceeds your original frame rate.
- Above 4× or below 0.5×, audio gets rough — Febler will suggest muting it.
Three steps. Zero fuss.
- 01
Add your videos
Drop one clip or many onto the page. MP4, MOV, WebM, MKV and TS are supported.
- 02
Set the speed
Drag the slider or tap a preset from 0.25× slow-mo to 8× hyper-lapse. Keep the audio or mute it.
- 03
Process & download
Watch live progress, then download your re-timed MP4 — no watermark.
Speed control that sounds right.
Voices keep their pitch
Audio is time-stretched, not just sped up — so fast speech stays natural instead of turning into a chipmunk.
A real range
From dramatic 0.25× slow-motion to 8× hyper-lapse, with a slider for every speed in between.
Private by design
Your video is processed inside your browser and never uploaded. No account, no server, no waiting.
Free and unlimited
No watermark, no daily cap, no file-size cap. Process as many videos as you like on any recent browser.
More free Febler tools
Quick fixes are just the start.
Let Febler edit it.
Febler AI is an agentic video editor — describe your idea and it cuts, adds B-roll, captions every word and finds your viral moments. No timeline. 100 free credits to start.
Full AI Edit
Turn raw footage into a finished short.
Auto B-roll
Matching footage on every sentence.
Easy Captions
Word-by-word animated subtitles.
Viral Clips
Your best moments, ready to post.
Video Speed Changer FAQ
How do I speed up or slow down a video online?
Drop your video onto the page, drag the speed slider or tap a preset (0.25× to 8×), and press the button. Febler re-times the video and gives you a new MP4 to download — free, with no watermark and no sign-up.
Is it free? Is there a watermark?
It's completely free with no watermark, no sign-up and no limit on how many videos you process or how big they are. The only ceiling is your own device's memory.
Is my video uploaded anywhere?
No. Everything happens inside your browser using WebCodecs and the open-source Mediabunny library. Your video never touches a Febler server, so it stays private.
Will the audio sound like a chipmunk when I speed it up?
No. Febler time-stretches the audio instead of just playing it faster, so voices keep their natural pitch — 2× speech sounds like someone talking fast, not squeaky. Slowing down works the same way — voices don't turn into a deep growl.
What speeds are supported?
From 0.25× (four times slower) up to 8× (eight times faster). Presets cover 0.25×, 0.5×, 0.75×, 1.25×, 1.5×, 2×, 4× and 8×, and the slider lets you dial in anything in between.
Should I keep or mute the audio?
Keeping audio sounds great from about 0.75× to 2×. Beyond that — especially above 4× — speech becomes hard to follow, so muting usually sounds better for time-lapses and hyper-lapses. Febler suggests the best option as you change the speed.
Does slow motion look smooth?
Slow motion stretches the frames you already have — it doesn't invent new ones. Footage shot at 60 fps or higher looks smoothest at 0.5×; 24–30 fps footage at 0.25× will look more stepped.
What happens to the frame rate when I speed up?
Febler drops frames as needed so the result never exceeds your original frame rate (capped at 60 fps). That keeps the file smooth and compatible everywhere.
Which formats are supported?
MP4, MOV, WebM, MKV and MPEG-TS (.ts / .mts / .m2ts). The result is saved as an MP4 that plays almost everywhere.
Can I change the speed of several videos at once?
Yes. Add as many as you like — they're processed one after another with live progress for each, and you can download them individually or all together.
What will the output file be called?
Your original name plus “-febler-ai-” and the speed, for example holiday-clip.mov at 2× becomes holiday-clip-febler-ai-2x.mp4, so you never overwrite the original.
Which browsers work?
The latest Chrome and Edge give the best results. Safari and Firefox work on versions that support WebCodecs. If your browser can't process the video, the page tells you.