Pay-as-you-go
Keep working past your monthly allowance, up to a cap you set.
By default, when you use up your monthly allowance, a paid plan falls back to its unmetered models on CPU until the next cycle. You keep working, but without the metered extras. Pay-as-you-go is the optional alternative: keep using metered models and runtimes past the allowance, up to a monthly cap you set.
How it works
Turn it on in Settings → Billing and set a monthly cap, the most you're willing to spend beyond your plan. With it on, metered work keeps going when the allowance runs out instead of falling back, and it keeps going until usage past the allowance reaches the cap. At the cap, metered work stops and you return to the unmetered CPU path.
The cap is the point. It's not an open tab. It's "let me go up to this much, no further."
When the cap applies
There is one spending guardrail: the monthly cap. A paid-plan run that starts inside the included allowance is allowed to finish even if it crosses that allowance. The next metered start then falls back unless pay-as-you-go is available.
Past the allowance, with pay-as-you-go on, the remaining cap behaves differently: it's a real ceiling, and it applies during a run, not just before it. A run that would carry you past the cap is stopped there.
How you're billed for it
Overage isn't charged as you go. It's totalled once the calendar month closes and billed on a separate Stripe invoice in the following cycle, so a run is never interrupted by a payment.
Two things are worth knowing. Each dollar of overage is bounded by the cap that was in force when you authorized it. With one unchanged cap, the invoice cannot exceed that number. Lowering the cap stops future overage at the new ceiling, but it does not erase usage already incurred under the earlier, higher cap. And only the month that just closed is invoiced: Clusy does not reach back and bill overage from earlier months.
Your current month's usage is always visible in Settings → Billing before it becomes an invoice.
Who can use it
Pay-as-you-go is a paid-plan feature, since it extends an allowance you already have. It isn't offered on the free tier, where the path to more is an upgrade, not a cap. See Plans.
Set the cap to a number you'd be fine paying
Treat the monthly cap as the amount you wouldn't mind being charged this month. Set it there and you get the convenience of not being interrupted mid-task, without an open-ended commitment.
Switch it off any time in Settings → Billing. On a paid plan the unmetered models and CPU keep working either way.