To reduce a video’s file size, shorten its duration, lower its bitrate, or reduce its resolution when the destination allows it. Start from the original project, change one setting at a time, and compare the result before uploading.
Simply renaming a file from MOV to MP4 does not compress it. The video must be exported or encoded with different settings.
Estimate the file size before exporting
For a rough decimal estimate:
File size in MB ≈ total bitrate in Mbps × duration in seconds ÷ 8.
Total bitrate includes video and audio. A 60-second clip at 8 Mbps video plus 0.192 Mbps audio is about 61.4 MB, before small container overheads. Variable bitrate and the way software reports megabytes can change the final figure.
If the same clip needs to fit below 30 MB, the total average bitrate must be below roughly 4 Mbps. Leave some room for overhead and variation rather than aiming exactly at the limit.
Remove unnecessary seconds first
Cut a long logo introduction, repeated explanation, or silent tail if it does not serve the video. Trimming a 60-second video to 45 seconds reduces its approximate size by a quarter at the same average bitrate.
This can preserve more visible detail than compressing an unnecessarily long edit very aggressively.
Do not make speech unnaturally fast just to save data. Edit the message instead.
Adjust bitrate with a short test
Bitrate describes how much data the file uses per second. Lowering it makes the file smaller, but fast motion, fine detail, and noisy footage can become blocky.
Export a difficult section first: moving water, a detailed product close-up, or a screen recording with small text. Compare the lower-bitrate export with your source at the expected viewing size.
If only the easy opening shot looks good, the setting is not ready for the whole video. See the video export guide for a broader explanation of bitrate choices.
Reduce resolution only when it makes sense
A 4K source may not need a 4K delivery file for every placement. Check the destination’s requirements, then test a smaller export while keeping the intended aspect ratio.
Resolution and bitrate work together. Changing the dimensions while leaving a very high bitrate may save less space than expected. Conversely, keeping a large frame with too little data can create obvious artifacts.
Avoid upscaling a low-resolution source in the hope that it will become sharper.
Choose a compatible codec
MP4 is a container; H.264 is a video codec. Their roles are different. YouTube’s encoding guidance recommends this combination for uploads.
Another codec may produce a smaller file at similar quality, but only use it when the actual platform and any scheduling tool accept it. Compatibility problems can cost more time than a smaller upload saves.
Check the result, not just the file size
Play the exported file from beginning to end. Inspect captions, faces, gradients, and transitions. Confirm that sound remains synchronized and that the file falls below the upload limit.
Keep the original master. If a second version is needed, export from that source rather than repeatedly compressing the smaller copy. Use the platform directory to check the destination before the final export.