A 601 s ad bills 11 Timeline minutes ($1.10) and misses TikTok's cap

Timeline 1.0 charges $0.10 for each ceil output minute, so a 600-second render costs $1.00 and a 601-second render costs ceil(601 / 60) = 11 minutes, $1.10. TikTok's video ad specification (read 2026-10-08) allows non-Spark ads of up to 10 minutes, so the extra second costs ten cents and also puts the file over the limit. Declare audio.duration_seconds: 600 or less.

The boundary, second by second

The reserve for a render is ceil(audio.duration_seconds / 60) minutes. The numbers below are straight from that formula and the $0.10 rate on the Timeline page (read 2026-10-08).

Keep a margin under the limit

A render of exactly 600 seconds sits on the line. If a file has a few frames of extra tail, the container length can be a little above 600 seconds. Declare 599 or 598 seconds: the price is still $1.00, and you have room. The last slot may stop at most 0.5 seconds before the end of the spine, so set the last slot's end to about the same value.

• The price is the same for 541 s and 600 s (10 minutes), so use the spare seconds.
• Check the output with duration_seconds in the job result.
• The TikTok page also lists a 500 MB cap and a 516 kbps floor; a 10-minute file at the floor is 38.7 MB.

Price per extra second

At the boundary the rate is lumpy. Going from 600 to 601 seconds adds $0.10 for one second. Going from 601 to 660 seconds adds nothing, because both bill 11 minutes. So when a file must run over a minute boundary anyway, use the rest of that minute for the tail of the ad, such as an end card, at no extra cost. When the boundary is a platform limit, as it is at 600 seconds for TikTok non-Spark ads, cut to the limit and do not use the spare minute.

The same arithmetic holds for any length: 60 seconds is one minute ($0.10), 61 seconds is two ($0.20), and 180 seconds is three ($0.30). The reserve at submit time is the same ceil, so a 601-second request also reserves $1.10 of credit.

What if the ad needs to be longer

The TikTok page (read 2026-10-08) says Spark Ads use mp4 or mov with no duration restriction; that is another ad type with its own rules. Timeline's own ceiling is 1,800 seconds, which would bill 30 minutes, $3.00. For a non-Spark ad, the answer to a 601-second file is a cut, and a single video trim of 600 seconds costs $0.02.