ConvertFast · 2026-09-06

How to split a large video into parts

Splitting creates separate clips from one recording. Choose equal parts when you need a specific number of clips, a fixed duration when each clip must fit a time limit, or manual cuts when the content should determine the boundaries. ConvertFast's Split Video tool provides these three planning modes.

Prepare the source

Use an MP4, MOV, AVI, MKV or WebM file already on your device. The interface rejects individual files larger than 500 MB. A supported extension does not guarantee that a browser can preview its internal codec. Keep the original recording until you have checked all the outputs.

If your file exceeds the limit, prepare a smaller source locally before uploading. The Video Compressor uses the same interface size limit, so it cannot be used to upload a file that is already too large for that limit. Network and hosting limits can also restrict practical upload size.

Split into equal parts

1. Open Split Video and select the source.
2. Wait for the browser to read its duration.
3. Choose Equal parts and enter a count from 2 to 50.
4. Generate the cuts and review the segment plan.
5. Select Start Conversion when the boundaries look right.

A ten-minute recording split into five parts has planned clips of about two minutes each. Equal time does not imply equal bytes: detailed scenes and movement may need more data than a static scene. Estimated sizes in the plan are approximate, and re-encoding changes the actual result. Minimum marker spacing can also reduce the number of cuts in a very short source.

Split by duration

Choose Fixed duration, enter an interval in seconds and generate the cuts. For a 95-second recording with a 30-second interval, the planned segments are 30, 30, 30 and 5 seconds. The last part can be shorter.

When the browser cannot preview the codec, the fallback duration field uses server-side stream copying. This can cut at nearby keyframes rather than exactly at the requested interval. Check each produced clip when a destination enforces a strict duration limit.

Choose manual cut points

Use manual markers for changes of topic, scenes or pauses. Review the timeline before starting so a sentence or action is not divided unintentionally. If you only need one section and want to discard the rest, Trim Video is the more direct tool.

Download and verify the parts

The server returns multiple MP4 parts together in a ZIP archive. A result containing only one segment is returned as MP4. Keep the browser tab open during upload and processing, then extract the ZIP on your device.

Play the beginning and end of every clip, check audio synchronization and confirm the sequence is complete. Splitting does not guarantee smaller total storage: re-encoded clips can occupy more space than the source. The timeline preview uses your local file, but actual splitting uploads it for server processing. See the Privacy Policy for storage behavior.

Related workflows

• Universal Video Downloader — retrieve a supported public source before uploading the saved file.
• Video Converter — prepare a compatible container and codec combination.
• Merge Videos — join compatible clips when one continuous file is needed.