💰 Free Tool

AI API Cost Calculator
Compare 30+ models

Enter your monthly usage and instantly compare costs across GPT-5, Claude 4, Gemini 2.5, DeepSeek, Mistral, Grok and more. Find the cheapest model for your workload.

Your Monthly Usage
Requests / month 10,000
1001M+
Avg input tokens / request 500
1008,000
Avg output tokens / request 200
504,000
Quick presets
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Cheapest option
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Total tokens / month
— / year
Monthly cost — sorted cheapest first
Model Input cost Output cost Monthly total

Prices as of May 2026. Costs are estimates — actual billing depends on exact tokenization and provider pricing tiers.
Verify at OpenAI, Anthropic, Google, DeepSeek.

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Frequently Asked Questions

Which AI API is cheapest in 2026? +
For most workloads, DeepSeek V3 ($0.27/1M input) and Gemini 2.0 Flash-Lite ($0.075/1M) are the cheapest capable models. For high-quality output, GPT-4.1 nano ($0.10/1M) and Mistral Small ($0.20/1M) offer excellent value. For reasoning tasks, DeepSeek R1 ($0.55/1M) is far cheaper than OpenAI's o-series.
How do I calculate AI API costs? +
Cost = (input_tokens × input_price_per_1M / 1,000,000) + (output_tokens × output_price_per_1M / 1,000,000). Multiply by your monthly request volume. Note that output tokens are typically 2–10× more expensive than input tokens, so minimising output length reduces cost significantly.
Does GPT-5 cost more than GPT-4o? +
GPT-5 at $1.25/1M input is actually cheaper than GPT-4o ($2.50/1M). GPT-5.5 costs $5/1M — 2× more than GPT-4o. For most applications, GPT-5 or GPT-4.1 offer a better cost-quality tradeoff than GPT-5.5.
How can I reduce my AI API costs? +
1) Use prompt caching — Anthropic and OpenAI offer 90% discount on cached tokens. 2) Optimise prompt length — remove unnecessary instructions. 3) Use smaller models for simple tasks. 4) Use the Batch API for non-real-time workloads (50% discount). 5) Store and reuse prompts with tools like PromptChief.
Is Claude 4 cheaper than GPT-4o? +
Claude Haiku 4.5 ($1/1M input) is cheaper than GPT-4o ($2.50/1M) for a more capable model. Claude Sonnet 4.6 ($3/1M) is slightly more expensive than GPT-4o but offers a 1M token context window at no extra charge.