Render a 20-minute Reel in one Timeline call: 1200 seconds, $2.00

A 20-minute Reel is 1200 seconds, which fits Timeline's 1 to 1800 second range. At $0.10 per ceil output minute it renders for $2.00. A third-party size guide, Postfa, read on 2026-10-06, lists 20 minutes as the Reels maximum and notes that Reels over three minutes are not recommended to new audiences.

What does the body need?

A voice file as audio.url with duration_seconds: 1200, or audio.mode: "silence" for a music-only piece, and up to 200 video[] slots whose starts increase from 0. Coverage can stop at most 0.5 seconds before the end of the spine; beyond that the compiler holds the last frame and warns.

Will a long render time out?

The default mode is async, so the submit returns a job. render.strategy defaults to auto, which chunks past 12 segments, and single above 12 is refused with render_strategy_unsafe. Poll GET /v1/jobs/:id/status or use the webhook.

Is 20 minutes the right length?

The last row shows the ceil rule: one extra second bills a whole extra minute.