At 40 requests/user/day (totaling 12,000 queries/mo), running AI coding assistant on Gemini 3.1 Pro costs $420.48 / month ($42.048 / user / mo).
Total expected API invoice for 10 Active Users generating 12,000 queries.
Direct inference cost per MAU to model your SaaS pricing tiers and gross margins.
Savings generated by exploiting 60% cache hits on prompt context.
| Model | Provider | Monthly Spend (10 Active Users) | Cost / User / Mo | Annual Spend | Context Limit |
|---|---|---|---|---|---|
| Gemini 3.1 Pro (Current) | $420.48 | $42.048 | $5,045.76 | 2,000,000 | |
| GPT-5.6 Sol | openai | $1,051.20 | $105.12 | $12,614.40 | 1,050,000 |
| GPT-5.6 Cyber | openai | $2,628.00 | $262.80 | $31,536.00 | 1,050,000 |
| GPT-5.5 Standard | openai | $1,051.20 | $105.12 | $12,614.40 | 512,000 |
| GPT-5.5 Pro | openai | $6,307.20 | $630.72 | $75,686.40 | 512,000 |
| o3-pro (Frontier Reasoning) | openai | $3,244.80 | $324.48 | $38,937.60 | 1,000,000 |
At 40 queries per user/day with Gemini 3.1 Pro, the estimated cost is $42.048 per monthly active user (MAU). Total monthly bill for 10 Active Users is $420.48.
Assuming a 60% cache hit rate on repeated system and context tokens, prompt caching saves $155.52 per month ($1,866.24/year) on Gemini 3.1 Pro.
With a direct COGS of $42.048 per user/month on Gemini 3.1 Pro, charging at least $210.24 per user/month ensures an 80%+ software gross margin.