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Free tool

AI API Cost Calculator

Estimate your monthly API spend across GPT-4o, Claude, and Gemini from your own usage — ranked cheapest-first. Free and instant.

1M tokens ≈ 750,000 words. Tip: a chatbot turn is often ~500–2,000 in / ~200–800 out.

  • GPT-4o minicheapest$4.50/mo
  • Gemini 2.5 Flash$15.50/mo
  • Claude Haiku$28.00/mo
  • Gemini 2.5 Pro$62.50/mo
  • GPT-4o$75.00/mo
  • Claude Sonnet 4$105/mo
  • Claude Opus 4$525/mo

Cheaper still: run a capable model locally for $0/token.

Approximate public list prices ($/1M tokens). Directional only — confirm current pricing with each provider.

Frequently asked

How is the AI API cost calculated?
Monthly cost = (requests × avg input tokens ÷ 1M × input price) + (requests × avg output tokens ÷ 1M × output price), summed for each model at its public per-million-token rate.
How many tokens is a typical request?
Roughly: 1M tokens ≈ 750,000 words. A single chatbot turn is often ~500–2,000 input tokens and ~200–800 output tokens, depending on context size.
How can I lower my AI costs?
Route cheap, short tasks to a smaller model (e.g. GPT-4o mini, Claude Haiku, Gemini Flash) and reserve the strong model for hard work — or run a capable open model locally for $0 per token.