Inference economics workbench

Q: Why measure cost per accepted task?

A lower token bill can come with more retries or human review. Divide the complete workflow cost by the original business tasks that meet your acceptance criteria, while also reporting failures and latency.

Q: Does the capacity calculator predict GPU performance?

No. Supply a tested per-replica request rate for your model, prompt and output distribution, and latency target. The calculator turns that rate and peak demand into whole replicas with explicit headroom and failure allowance.

Q: Are my inputs uploaded?

The web calculators run in your browser. Saving a scenario downloads a JSON file locally. The separate calculation API is optional and does not store inputs.

Seven free calculators for API budgets, fleet cost, peak capacity, API-versus-fleet break-even, cache reuse, human review and hardware ownership. Change the assumptions and save your scenario.

7 calculators · no account needed

Change the assumptions, inspect the formula and save your scenario. The starting numbers are teaching examples. Calculations stay in your browser.

Your calculation

Billable attempts: 1,080,000 attempts
Model charges: 11,880 USD
Other attempt-based charges: 1,080 USD
Other monthly cost: 2,000 USD
Total cost: 14,960 USD
Accepted business tasks: 900,000 tasks
Cost per accepted task: 0.016622 USD / task

Compare the amounts

Model charges11,880 USD

Other attempt-based charges1,080 USD

Other monthly cost2,000 USD

All bars start at zero. Values come from the inputs above.

How the result is calculated

Attempts = tasks × calls per task × attempts per call. Spend = attempts × (sum of tokens × category price / 1,000,000 + tool cost) + fixed cost.

Default inputs are hypothetical. Include reasoning in billable output where your provider charges for it. Put cache storage and other monthly charges in fixed cost. Acceptance is measured per original business task.

Read the Cost-per-Token Playbook →
The guide explains the assumptions and works through full business scenarios. Selected pages are free; the complete PDF and offline companion are included with Premium.

Use the result to make a decision

A useful budget connects a business task to the calls it creates, the capacity those calls need and the outcomes the product accepts. Use the same workload and quality target when comparing options. Each calculator shows its formula and the conditions that could change the decision.

Questions people ask

Are the starting values current vendor prices?▲

The calculator defaults are hypothetical teaching inputs. Replace them with your invoice or quote. The linked playbook includes a dated register of selected public prices and explains the billing units.

Why measure cost per accepted task?▼

Does the capacity calculator predict GPU performance?▼

Are my inputs uploaded?▼