Turn a registered-user count into active usage, model calls and billable tokens. Compare an uncached baseline with a stated caching scenario without inventing a vendor quote.
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All figures, including prices, are fictional planning assumptions. Retry calls have the same token shape as primary calls in this base case. Estimate the model bill separately from full operating costs.
| Registered users | 10,000,000 |
|---|---|
| Monthly active share | 20% |
| Tasks per active user per month | 8 |
| Primary model calls per task | 2 |
| Extra retry calls as share of primary calls | 5% |
| Input tokens per call | 1,500 |
| Output tokens per call | 300 |
| Uncached input price per million tokens | $2 |
| Output price per million tokens | $8 |
| Successfully completed share of attempted tasks | 90% |
| Separate cache scenario | 40% of input tokens are qualifying hits at a 75% discount; no additional cache-write or storage charge in this fictional tariff. |
Your task. Calculate monthly calls, input and output volumes, the uncached and cached model bill, and cost per successful task. Identify the next assumptions to measure and the missing capacity and operating-cost inputs.
Turn a registered-user count into active usage, model calls and billable tokens. Compare an uncached baseline with a stated caching scenario without inventing a vendor quote.
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