概要 動画結合
Combine multiple clips into a single video without uploading anything. Add your files, drag them into the right order, and the merger decodes every clip, scales it to a common resolution and joins the frames and audio into one continuous file — MP4 (H.264/AAC) or WebM (VP9/Opus).
Mixed inputs are handled automatically: different resolutions are letterboxed to the output size and different codecs are uniformly re-encoded, so the result plays seamlessly everywhere. Everything runs locally via WebCodecs — your clips never touch a server.
使い方 動画結合
- Add your clips
Drop two or more videos. Each is analysed and listed with its resolution and duration.
- Set the order and output
Reorder clips with the arrows, then choose the output resolution (same as first video, 1080p, 720p or 480p), format and quality.
- Merge and download
Press Merge videos. Progress is shown per clip; preview the joined result and download it as a single file.
よくある質問
Can I merge videos with different resolutions or formats?
Yes. Every clip is decoded and normalized: different resolutions are scaled into the output frame with black letterboxing, and all clips are re-encoded with the same codec, so the merged file plays without gaps or glitches.
Why is merging slower than trimming?
Safe concatenation requires re-encoding every clip into a common format. The speed depends on your device — modern laptops with hardware-accelerated WebCodecs encoders typically process several times faster than realtime.
How many clips can I merge at once?
Up to ten clips per merge. Practical limits depend on total duration and your device's memory, since all processing happens locally in the browser.