Why is video so heavy?
Video is dozens of images per second strung together, so it's far larger than a photo — and easily trips email (often 25MB) or messenger limits. The good news: re-encoding can cut size a lot without hurting quality much.
视频压缩直接在浏览器中压缩视频文件。立即使用CRF: balancing quality and size
Lower CRF means better quality and larger files; higher means smaller. Around 23 is the usual sweet spot. For archiving or sharing, you can push to 26–28 with little visible impact and a smaller file. If quality is critical, drop to 20–22.
Use the compatible H.264 codec
H.264 (MP4) is the safe default because it plays almost everywhere. If you only need the sound, extract the audio as MP3 to shrink the file dramatically.
About processing speed
This tool encodes inside your browser instead of sending the video to a server, so processing time depends on the clip length and your device. In exchange, even sensitive footage never leaves your device. Got photos to shrink too? Try the image compressor.