動画圧縮

Why compress a video?

Smaller videos upload faster, embed cleanly in chat apps, slip past 25 MB email caps, and stream more reliably on slow connections. Marketers fitting case-study clips into Slack, support teams attaching reproductions to tickets, sales reps sending demo recordings, and creators hitting Twitter / X size caps all benefit from a quick on-the-fly compression pass.

Step-by-step

1. Upload a video from your device or paste a direct URL.
2. Pick Basic mode for a quick target file size, or Advanced mode for full control over resolution, codec, bitrate, frame rate, and audio.
3. Adjust the resolution downscale — lower resolutions shrink the file fastest with the smallest perceived quality loss.
4. Choose H.264 for universal playback, H.265 for ~30 % smaller files at the same quality, or AV1 when both sender and recipient run modern browsers.
5. Optionally remove the audio track or strip metadata when sharing the video publicly.
6. Click Compress Video, watch the progress bar, preview the result, then download the file or compress another.

What each part of the interface does

Select Video panel hosts the input mode tabs: upload from device for full local processing, or paste a remote URL when the video already lives on a public server. The card shows the loaded clip's size, duration, and resolution as soon as decode completes.

Compression Settings exposes Basic mode (a single target file size in MB) and Advanced mode (resolution preset, codec selector, video bitrate, frame rate, remove audio toggle, strip metadata toggle).

Original / Compressed previews render side by side after encoding finishes so you can sanity-check the size reduction and quality before downloading.

When to flip each option

• Resolution — drop from 1080p to 720p when sending demos or screencasts; halving each axis can shave 50–70 % off without obvious quality loss.
• Codec — H.264 for compatibility, H.265 for smaller files in modern browsers, AV1 for the smallest archival result.
• Bitrate — leave on Auto unless you need a specific upload cap; manual bitrates below 800 kbps tend to introduce blocky artefacts at 720p+.
• Frame rate — drop to 24 fps for talking-head or screencast content; keep 60 fps only when motion is the point (gameplay, sports).
• Remove audio — turn on for silent demos or looping clips; saves both size and re-encoding time.
• Strip metadata — keep on by default when sharing publicly; removes EXIF-style tags, GPS, and editor fingerprints.

Tips that save real time

• A target size much smaller than the source forces a low bitrate. If quality drops too far, raise the target or step the resolution down instead of chasing the bitrate floor.
• Speech-only clips compress much further when you drop the frame rate to 24 fps and choose a lower resolution.
• Re-encoding loses information. Compress once from the highest quality master rather than chaining multiple passes.
• For email attachments under 25 MB, start with 720p + H.264 + Auto bitrate — that combination clears most providers' inbox limits in one pass.
• For social uploads, pick the platform's native short-side cap (1080 for Instagram Reels, 1280 for Twitter, 1920 for YouTube) before clicking Compress.