How to Compress a Video for YouTube

The right way to compress a video for YouTube is to target the bitrate YouTube publishes rather than a file size you picked. For 1080p SDR that's 8 Mbps at standard frame rates and 12 Mbps at high frame rates.

Compress a video for YouTube to the recommended bitrate

Multiply that bitrate by your runtime and you have the file size you should be aiming at. Going under it means handing YouTube a degraded source, which it will then re-encode, so the loss is permanent and compounded. Going far over it mostly wastes your upload time, because the transcode happens regardless.

The rest of YouTube's recommended encode is specific enough to paste into an export dialog: H.264, progressive scan with no interlacing, High Profile, two consecutive B frames, closed GOP, CABAC, and variable bitrate.

The audio is not where you save space

There's a persistent instinct to drop audio quality when a file is too big. It's the wrong lever: audio is a small share of a video file's size, and it's the part viewers notice fastest.

YouTube asks for AAC-LC or Opus, in stereo or stereo plus 5.1, at a 48 kHz sample rate. Meet that and move on. The savings you were looking for are in the video stream, in the frame size, or in the runtime.

One export, already in an efficient codec

Montaj exports HEVC in an .mp4 container. HEVC compresses more efficiently than H.264 at comparable visual quality, which means the file coming out is already reasonably lean without a separate compression pass bolted on afterwards.

That matters mostly for what it prevents: a second encode. Editing on the device, exporting once, and uploading that file avoids the extra generation of loss that a compress-after-export workflow introduces. It's a shorter route to the same place as trying to compress a video for YouTube once you've already exported it.