At 4 requests/user/day (totaling 12,000,000 queries/mo), running Document summarization on OpenRouter Auto-Best Router costs $321,600.00 / month ($3.216 / user / mo).
Document summarization for a 100,000 active users (high-volume consumer / enterprise) audience means 400,000 requests per day on average, each carrying 25,000 input and 600 output tokens at a 10% cacheable share — so the effective per-request cost on OpenRouter Auto-Best Router is $0.0268, of which $0.00/mo comes back from prompt caching. Per active user that's $3.216/mo — the number to hold against your pricing tier and gross margin. Charging at least $16.08/user/mo keeps gross margin at or above 80%.
Quick answer
For 100,000 Active Users, Document summarization on OpenRouter Auto-Best Router is modeled at 12,000,000 requests per month, costing $321,600.00 per month or $3.216 per active user.
Method & trust
This projection combines the selected active-user tier, requests per user per day, input/output tokens per request, and the modeled cache share. It is an operating estimate, not a provider invoice; production traffic and retries should be measured against it.
Total expected API invoice for 100,000 Active Users generating 12,000,000 queries.
Direct inference cost per MAU to model your SaaS pricing tiers and gross margins.
Savings generated by exploiting 10% cache hits on prompt context.
| Model | Provider | Monthly Spend (100,000 Active Users) | Cost / User / Mo | Annual Spend | Context Limit |
|---|---|---|---|---|---|
| OpenRouter Auto-Best Router (Current) | openrouter | $321,600.00 | $3.216 | $3,859,200.00 | 1,000,000 |
| GPT-5.6 Terra | openai | $632,400.00 | $6.324 | $7,588,800.00 | 1,050,000 |
| GPT-5.4 Workhorse | openai | $790,500.00 | $7.905 | $9,486,000.00 | 256,000 |
| o3-mini | openai | $345,180.00 | $3.452 | $4,142,160.00 | 200,000 |
| o4-mini | openai | $336,930.00 | $3.369 | $4,043,160.00 | 256,000 |
| o1-mini | openai | $345,180.00 | $3.452 | $4,142,160.00 | 128,000 |
At 4 queries per user/day with OpenRouter Auto-Best Router, the estimated cost is $3.216 per monthly active user (MAU). Total monthly bill for 100,000 Active Users is $321,600.00.
Assuming a 10% cache hit rate on repeated system and context tokens, prompt caching saves $0.00 per month ($0.00/year) on OpenRouter Auto-Best Router.
With a direct COGS of $3.216 per user/month on OpenRouter Auto-Best Router, charging at least $16.08 per user/month ensures an 80%+ software gross margin.