Song limited to 90 seconds in a 165-second Short: plan the audio

If a song is limited to 90 seconds in a Short, build the audio so the song fills only the first 90 seconds and another sound fills the rest. For a 165-second Short that means 90 s of song plus 75 s of voice or a bed, joined with timeline audio concat for $0.01, then one Timeline 1.0 render for $0.30. Total $0.31 at the rates in the Sume catalog.

The rule comes from YouTube's own Shorts page (read 2026-10-09): on standard channels "you can use most songs for up to 90 seconds in a 3 minute Short. However, some tracks may be limited to 60 or 30 seconds." The same page says a Short over one minute with an active copyright claim of any type is blocked globally and cannot be monetized. This post is about the media plan, not about whether your track is cleared.

What the page gives you

Three song caps (90, 60, 30 seconds) and one length line (3 minutes). The page says some tracks may be limited to 60 or 30 seconds, so treat 90 as the best case and plan the worst case you can see for your track. The page does not say how the cap is shown, so check the track in YouTube itself before you build the file.

Build the audio spine

Timeline audio takes 1 to 20 ordered parts. Each part is a URL with an optional source_in and duration, and all parts must share a channel layout (audio_parts_channel_mismatch). The result is one wav (default, sample-exact) plus segments[] offsets you can use to place video slots. Import both files to media.sume.com first; the API does not fetch from the open internet.

The body below joins the first 90 seconds of the song with 75 seconds of a bed. Send it to POST /v1/timeline-1.0/audio with an Idempotency-Key.

{
  "operation": "concat",
  "parts": [
    { "url": "https://media.sume.com/artifacts/artf_demo/song.wav", "source_in": 0, "duration": 90 },
    { "url": "https://media.sume.com/artifacts/artf_demo/bed.wav", "source_in": 0, "duration": 75 }
  ]
}

Placing the picture

The picture does not have to follow the song split. Timeline video[] slots are placed on the audio spine by start time; video[0].start must be 0 and later starts must increase. If your segments are 0 to 90 s of footage over the song and 90 to 165 s of footage over the bed, use the concat result's segments[] offsets (index, start, duration_seconds) as the starts. Declared starts are authoritative, so you can also ignore the offsets and cut on the beat.

Render and cost

Use the joined file as audio.url on a Timeline 1.0 render with audio.duration_seconds 165. Timeline bills $0.10 per output minute, rounded up, so 165 seconds is ceil(2.75) = 3 minutes = $0.30. Add the $0.01 concat job and the plan is $0.31 before any trims. The unbilled POST /v1/timeline-1.0/plan call returns billable_minutes and estimated_cost_usd_micros so you can confirm that number first.

Two cautions. First, if the song cap turns out to be 30 seconds, change the first part's duration to 30 and the bed to 135; nothing else moves. Second, a 165-second Short is over the one-minute line, so the claim rule above applies to it; if you cannot clear the track, cut a version of 60 seconds or less instead.

• Concat: $0.01 flat per job
• Render: $0.10 x 3 minutes = $0.30
• Spine limit: 1,800 s; this plan uses 165 s