A base fee, the compute you reserve, the seconds you use.
Prepaid credits, spent per second of the compute a solve reserves. You pick the engine, the compute preset it runs on and the runtime; the maximum cost follows from those three and is known before you submit.
How a solve is priced
cost = base_fee + ceil(seconds × effective_rate)
Three things set the price. The engine's base fee, charged once per solve. Its runtime rate, in credits per second of reserved compute. And the compute preset you run on, which multiplies that rate: the effective rate is the engine's rate times the preset's multiplier. The rate card below prints the effective rate for every engine on every preset it offers.
The maximum cost is known before you submit
Take the effective rate, multiply by the runtime you set, round up, add the base fee. That is the most the solve can cost, and it is what is reserved from your balance when the problem is admitted. You pay the seconds you used, never more. Queue time is never billed, a solve that never starts costs nothing, and a cancelled one costs the seconds it ran.
A solve that runs s seconds on an engine with base fee b at an effective rate r costs b + ceil(s × r) credits.
The terms you submit at are the terms you pay: the base fee, the rate and the preset's multiplier are captured with your submission, so a later price change never touches a solve in flight. The meter is the time your solve held the compute, measured on our clock from the moment an engine picks the problem up to the moment it ends and capped at the runtime you set. It comes back with the solution and it is itemised on your ledger.
No engines are published on this site yet.
Billing, honestly
Is a proven-infeasible result billed?
Yes. The solver worked and the proof is the product: knowing a plan is impossible is exactly as valuable as a plan. It is billed like any solve, for the time consumed.
What if a solve crashes mid-run?
Not your problem, not your bill. The solve is detected and re-queued automatically, and picked up again. Only the successful attempt is metered. Our failures are free.
What does cancelling cost?
The seconds consumed until the cancellation, never more. A problem cancelled while still queued is free, and the whole reservation goes back to your balance.
Which compute preset should I pick?
The cheapest one that finishes your model in time. A larger preset costs more per second, so it pays only when the extra cores or memory shorten the solve by more than the multiplier. Each engine names the presets it runs on, and one of them is its default.
How do I verify what I was charged?
Every solution carries its metering report, every ledger entry links its problem, and the formula above is the whole formula. Your bill is reconstructable from data you hold.
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