Change Video Speed
0.25× slow motion to 4× time-lapse — voices keep their natural pitch
Audio is time-stretched (atempo), so voices keep their natural pitch — or remove the audio entirely.
Server-side FFmpeg handles any format — including HEVC/H.265 files your browser can't play. Files are deleted from the server within 30 minutes.
⚠️ Please don't close or refresh this page until it's done, or you may lose the result.
選ばれる理由
Server-grade processing
Real FFmpeg on dedicated hardware: every format, big files, phone stays cool — no browser limits.
Auto-deleted in 30 min
Uploads and results are wiped from the server within 30 minutes. Nothing is kept, shared or used for training.
Pay with credits
Each job costs a few credits from your balance — free accounts get daily credits too. No hidden fees.
使い方
- 1
Upload a video and pick a speed from 0.25× to 4×.
- 2
Keep the audio (pitch-corrected) or remove it entirely.
- 3
The server re-encodes — download the MP4. Files auto-delete in 30 minutes.
よくある質問
Will sped-up voices sound like chipmunks?⌄
No — the audio goes through atempo, a time-stretching algorithm that changes speed without changing pitch. A 2× voice still sounds like the same person, just faster.
Does slow motion add new frames?⌄
No frame interpolation is done — each frame simply stays on screen longer, so 0.25× from low-frame-rate footage can look steppy. Buttery slow motion needs high-frame-rate source material.
What happens to my file?⌄
Both the upload and the result are deleted automatically within 30 minutes. Only your session's signed token can access the job.
関連ツール
関連ツール
Cloud Video Compressor
Server-grade MP4 compression for any format — HEVC, MKV, 1 GB files, no browser limits
Cloud Video Trimmer
Frame-accurate cutting on the server — any format in, clean MP4 out
Cloud GIF Maker
Palette-optimized GIFs from any video — FFmpeg's best two-pass quality