API Cost Calculator
Calculate your AI API costs for GPT-4, Claude, and other LLMs.
Usage Parameters
Current Pricing: Input: $0.01/1K tokens, Output: $0.03/1K tokens
Monthly Estimated Cost
$75.00
$0.0250 per request
Cost Breakdown
API Cost Calculator Guide
This calculator estimates the cost of sending prompt tokens and receiving output tokens from an AI API. It is useful for pricing prototypes, setting monthly budgets, and comparing whether prompt changes or model changes reduce cost.
Pricing changes over time, and providers may bill inputs, cached inputs, outputs, images, audio, tools, or batch processing differently. Treat the result as a planning estimate unless the page is updated to match the exact provider schedule you use.
How to Use It
- Estimate or measure input tokens per request.
- Estimate expected output tokens.
- Enter average daily request volume.
- Check cost per request, then scale it to daily, monthly, and yearly usage.
Cost Formula
Most text API pricing can be modeled with a simple token-based formula.
Estimated Request Cost
Where:
- Input Tokens= Prompt and context tokens sent to the model
- Output Tokens= Tokens generated by the model
- Input Rate= Provider price for input tokens
- Output Rate= Provider price for output tokens
What Often Pushes Costs Up
Long system prompts, repeated retrieved context, verbose JSON output, retries, tool calls, and streaming-heavy workflows can all raise cost faster than expected. In production, the cheapest improvement is often shorter context, better caching, or using a smaller model where quality remains acceptable.
Worked Examples
Cost per Request
Problem:
A workflow sends 3,000 input tokens and gets 800 output tokens.
Solution Steps:
- 1Multiply input tokens by the current input rate
- 2Multiply output tokens by the current output rate
- 3Add both values for the request total
Result:
This gives a planning estimate for one request before daily volume is applied.
Monthly Budgeting
Problem:
A team expects 2,000 requests per day.
Solution Steps:
- 1Estimate one-request cost first
- 2Multiply by daily request count
- 3Multiply the daily total by roughly 30 days for a monthly projection
Result:
This makes it easier to set alerts and spending limits before launch.
Tips & Best Practices
- ✓Use live token counts from production logs when possible.
- ✓Keep a separate estimate for retries and failed requests.
- ✓Measure whether shorter prompts preserve quality before rolling them out.
- ✓Review official pricing regularly because rates and model names change.
Frequently Asked Questions
Sources & References
Last updated: 2026-05-20
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Editorial Note
MyCalcBuddy Editorial Team
This page is maintained as an educational calculator reference.
Formula Source: Standard Mathematical References
by Various