At 4 requests/user/day (totaling 12,000 queries/mo), running Document summarization on GPT-5.5 Pro costs $9,486.00 / month ($94.86 / user / mo).
Total expected API invoice for 100 Active Users generating 12,000 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 Active Users) | Cost / User / Mo | Annual Spend | Context Limit |
|---|---|---|---|---|---|
| GPT-5.5 Pro (Current) | openai | $9,486.00 | $94.86 | $113,832.00 | 512,000 |
| GPT-5.6 Sol | openai | $1,581.00 | $15.81 | $18,972.00 | 1,050,000 |
| GPT-5.6 Cyber | openai | $3,952.50 | $39.525 | $47,430.00 | 1,050,000 |
| GPT-5.5 Standard | openai | $1,581.00 | $15.81 | $18,972.00 | 512,000 |
| o3-pro (Frontier Reasoning) | openai | $6,036.00 | $60.36 | $72,432.00 | 1,000,000 |
| o3 (Reasoning Frontier) | openai | $3,018.00 | $30.18 | $36,216.00 | 1,050,000 |
At 4 queries per user/day with GPT-5.5 Pro, the estimated cost is $94.86 per monthly active user (MAU). Total monthly bill for 100 Active Users is $9,486.00.
Assuming a 10% cache hit rate on repeated system and context tokens, prompt caching saves $810.00 per month ($9,720.00/year) on GPT-5.5 Pro.
With a direct COGS of $94.86 per user/month on GPT-5.5 Pro, charging at least $474.30 per user/month ensures an 80%+ software gross margin.