Max video length in October 2026: TikTok, YouTube Shorts, Sume tools

Short answer

TikTok's Content Posting API accepts video up to 10 minutes, though an end user may be limited to 3, 5 or 10. YouTube Shorts run up to 3 minutes if square or vertical. On the Sume side the limits depend on the tool: 1800 seconds for a timeline and for inspect, 900 seconds for a trim output, and 300 seconds for video frames and video filter sources.

The limits in one table

Platform rows come from the pages I read on 2026-10-05. Sume rows come from the docs in the repo.

What that means for one master

A 10-minute vertical video is a valid TikTok upload and not a Short. To make a Short from it, cut 180 seconds or less with video trim. To post it on TikTok for a 3-minute account, split it first. The timeline route is the only one that assembles clips, and it takes up to 1800 seconds, so one 10-minute build is 600 seconds and 10 billable minutes, or $1.00 at the documented rate.

The frames and filter routes are the odd ones out. A source over 300 seconds has to be trimmed before frames or filters can use it, so plan a trim as step one on long files.

A lookup function

This pure function returns the Sume routes that accept a source of a given length, so a pipeline can decide whether to trim first. It encodes only the limits in the table, and it is a sketch to adapt: your own pipeline will also care about file size, format and price.

LIMITS = {"timeline": 1800, "trim": 1800, "inspect": 1800,
          "frames": 300, "filter": 300}

def routes(seconds):
    ok = [name for name, cap in LIMITS.items() if seconds <= cap]
    return ok or ["trim into parts first"]

for secs in (180, 600, 1200, 2400):
    print(secs, routes(secs))

Check before you build

Probe every source with video inspect and frames set to false so you get the probe and its duration without stills. Then pick the route from the function. Platform limits can change, so reread the vendor page before a large run. Both the TikTok guide and the YouTube Shorts page were read on 2026-10-05, and that is the date to treat as the last check.

Two cautions. The TikTok per-account limit is not a constant, so a number like 10 minutes in the API reference does not tell you what a given user can post. And the Sume limits above are the ones in the repo docs today, which the live catalog and OpenAPI can supersede. When a job is refused, the error code names the limit that was hit, for example source_duration_exceeded on a trim of a source longer than 1800 seconds.