Shotstack overage at a 30% premium vs Sume's 402 before work starts

When a Shotstack account runs out of credits, what happens depends on the plan: its pricing page says subscribers keep rendering and are charged overage at a 30% premium to their plan rate, while pay-as-you-go accounts stop working until more credits are bought. Sume behaves differently by design: its docs say a paid submit returns 402 insufficient_credits before provider work starts if the balance cannot cover the estimate.

What does Shotstack's page say about running out?

The FAQ answer reads: on a subscription, videos and images continue to render, and credits used in excess of the allowance are charged as overage at the end of the billing cycle at a 30% premium to the rate in the plan. On a pay-as-you-go plan the API stops functioning until you purchase more credits. The page lists $0.30 per minute for pay as you go and $0.20 per minute for the subscription, with one credit equal to one minute of video, rounded down to the second.

How does Sume admit a job instead?

Sume admits paid work with a reserve step. The generation-admission page says a submit creates a durable job only when the request is valid, the balance can be reserved, and the workspace has accepted-job capacity. If the estimated cost cannot be reserved, the submit fails with 402 insufficient_credits, and the page tells you to upgrade the plan, wait for included Gen$, or submit a cheaper request.

On success the reserved amount is captured; failed jobs and failed queue admission release or refund the reservation where applicable. Cancel works only before generation starts.

What does a Sume render cost for the same 90 seconds?

Timeline 1.0 is Sume's assembly route: an audio spine plus ordered video clips become one MP4. Its public rate is $0.10 per ceil(output minute), so a 90-second output bills two minutes, $0.20, and the reserve is ceil(audio.duration_seconds / 60) minutes. The docs note there is no provider inference in this step, only worker ffmpeg.

That figure is for assembly only. Shotstack's rate covers its own editing and rendering, and any generated clips on Sume are priced on their own surfaces, so do not read the two headline rates as the cost of the same finished product.

What should a budget guard check?

For Shotstack subscriptions, the risk is silent overage at a higher rate, so track credits used against the allowance before month end. For pay as you go, the risk is a hard stop, so watch the balance. On Sume the failure arrives at submit time as a 402 with a request id, which a script can catch before any work is queued.

One more difference: Shotstack's page lists a one-year validity for pay-as-you-go credits and rollover of up to three times the monthly allowance for subscribers. Check the live page before you rely on either rule, since billing terms change and this snapshot is dated.