AI API budget for a startup MVP
A realistic monthly AI API budget for an early product, with live prices across small and flagship models.
Estimated monthly cost — Mixed MVP traffic
Calculated live from current TokenRex prices.
| Model | Input / 1M | Output / 1M | Per month |
|---|---|---|---|
| GPT-6 Luna | $0.10 | $0.50 | $22.50 |
| Claude Haiku 4.5 | $1.00 | $5.00 | $225.00 |
| Gemini 3.8 Flash | $0.75 | $3.75 | $168.75 |
| Gemini 3.1 Flash Lite | $0.25 | $1.50 | $62.50 |
| GPT-6 Sol | $2.00 | $10.00 | $450.00 |
| GPT-6 Astra | $10.00 | $50.00 | $2.3k |
| Claude Opus 5.5 | $4.00 | $20.00 | $900.00 |
| Claude Sonnet 5 | $2.00 | $10.00 | $450.00 |
| Gemini 4 Argon | $2.00 | $10.00 | $450.00 |
The workload we priced
50,000 requests a month, each with about 2,000 input tokens and 500 output tokens. One token is roughly three quarters of an English word.
What drives the bill
Start with a small model as the default and route only hard requests to a flagship.
Track spending per feature from the usage field in each response.
Questions
- Are these exact monthly bills?
- They are estimates from live TokenRex prices and the token counts shown. Real bills depend on your actual prompt and reply lengths, which every API response reports in its usage field.
- How do I lower the cost?
- Shorten system prompts, cap reply length, cache repeated input where the model supports it, and send simple requests to a smaller model.
- Which currency am I billed in?
- Wallet top-ups and billing are in Indian rupees. Prices display in US dollars by default, and signed-in users can choose another display currency.
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