TikTok upload chunk size: 5-64 MB and 1000 chunks for AI video

Pick a chunk size between 5 MB and 64 MB so the file needs at most 1000 chunks; TikTok's guide sets the maximum video size at 4GB. Sume's docs state no output file size, so read the MP4's size from its media.sume.com URL before you plan chunks.

What are TikTok's chunk rules?

The guide says "Each chunk must be at least 5 MB but no greater than 64 MB, except for the final chunk, which can be greater than chunk_size (up to 128 MB)." It also says "There must be a minimum of 1 chunk and a maximum of 1000 chunks."

How do I estimate the chunk count?

Divide the file size by the chunk size you choose and round down, because the final chunk may be larger than the others. As an example, a 300 MB file at 64 MB chunks gives four full chunks plus a final chunk that absorbs the remaining 44 MB. Keep the count between 1 and 1000; at the 5 MB minimum a 4GB file would come close to that limit, so a larger chunk is the easier choice.

How do I read the size of a Sume MP4?

A finished trim or timeline job returns a video_url on media.sume.com. Sume's docs do not show a file size field on the result, so download the file (or ask the host for its length) and measure it yourself. The docs do not describe a size or bitrate setting, and fields such as codec or crf are refused as ffmpeg_fields_rejected, so the only lever is the content itself: length, output width and height (256 to 2160 on trim and timeline) and fps.

What can I change to make a file smaller?

Shorten the range with https://docs.sume.com/models/video-trim, or lower the output width and height and pick a lower fps (24, 25, 30 or 60). The docs do not say how much either reduces the file, so measure again after the change.

What is uncertain here?

The examples above are arithmetic on TikTok's quoted numbers. Whether your account's upload needs a specific chunk size is decided by the initialize call; follow the response you get.

What is a practical rule?

Choose a chunk size near the top of the allowed range for large files and near the bottom for small ones, then check that the count stays inside 1 to 1000. Keep the final chunk's larger allowance in mind: it can carry the remainder rather than forcing a tiny last piece.

• Measure the finished MP4 once, after the Sume job succeeds.
• Pick chunk_size from the 5 MB to 64 MB range.
• Confirm the count is between 1 and 1000.
• Upload in order and let the last chunk take the remainder.