Reasoning Token Cost Calculator
Account for hidden reasoning tokens on o-series and thinking models.
With the default inputs, $0.0220 per request — Hidden reasoning adds $0.0160 (72.7%) per request. Enter your own numbers below to recompute instantly; the full step-by-step math is shown under the worked example.
Results update automatically as you type.
- • Reasoning models bill hidden reasoning tokens at the output rate.
- Visible output tokens
- 500 tokens
- Reasoning tokens (billed)
- 2,000 tokens
- Cost with reasoning
- $0.0220
- Reasoning overhead / request
- $0.0160
- Reasoning overhead / month
- $800.00
Reasoning models generate hidden 'thinking' tokens that are billed at the output rate but you never see. Estimate how much that reasoning overhead adds per request and per month.
How this is calculated
Total output billed = visible output + hidden reasoning tokens, both charged at the model's output rate; input is priced separately. We add the reasoning overhead you specify so the per-request and monthly cost reflect what you actually pay, not just the answer you see.
Is this a good result? What to do next
Reasoning tokens are invisible but real — on hard tasks they can dwarf the visible answer. If your bill is higher than the visible output suggests, hidden reasoning is usually why. Pull real reasoning-token counts from your provider's usage dashboard.
Typical planning ranges
- Reasoning tokens
- hundreds to many thousands / request
- Billing
- at the output rate
- Variability
- scales with task difficulty
Ranges are typical planning figures to sanity-check your result, not authoritative benchmarks. Your numbers will vary with use case, volume, and vendor.
How to improve this number
- Lower the reasoning effort/verbosity where the model supports it.
- Use a non-reasoning model for easy tasks.
- Route by difficulty so reasoning is spent only where it helps.
Common mistakes
- Budgeting only visible output on reasoning models.
- Assuming a fixed reasoning-token count across all tasks.
When to use a different approach
For plain generation, use the output token cost calculator. To weigh reasoning vs standard models, use the model cost comparison.
Worked example (defaults)
With the default inputs above, here is the result:
- • Reasoning models bill hidden reasoning tokens at the output rate.
- Visible output tokens
- 500 tokens
- Reasoning tokens (billed)
- 2,000 tokens
- Cost with reasoning
- $0.0220
- Reasoning overhead / request
- $0.0160
- Reasoning overhead / month
- $800.00
Sources & references
Frequently asked questions
What are reasoning tokens?+
Internal chain-of-thought tokens that reasoning models produce before the final answer. They're billed as output tokens even though they're hidden.
How many reasoning tokens are typical?+
It varies widely by task — from a few hundred to many thousands. Check your usage dashboard for real numbers.
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