System Prompt Cost Calculator
See what a fixed system prompt costs at scale.
Results update automatically as you type.
Result
$300.00/month
Your 800 tokens system prompt, sent every request
- System prompt tokens
- 800 tokens
- Cost per request
- $0.00100
- Cost per month
- $300.00
A system prompt is re-sent on every request, so a long one quietly adds up. Enter its size and your volume to see the monthly cost, and how caching changes it.
How this is calculated
This calculator uses the api cost formulas described in our methodology. All figures are estimates for planning; verify current pricing with each provider before relying on them.
Worked example (defaults)
With the default inputs above, here is the result:
Result
$300.00/month
Your 800 tokens system prompt, sent every request
- System prompt tokens
- 800 tokens
- Cost per request
- $0.00100
- Cost per month
- $300.00
Frequently asked questions
Should I cache my system prompt?+
Yes, if your provider supports it and the prompt is stable. Caching a long system prompt can cut its cost by ~90%.