Free LLM API cost calculator

How LLM token cost is actually calculated

Every provider prices per token rather than per request, and input and output are billed at different rates — output is typically several times more expensive. So an LLM token cost calculator is really doing one piece of arithmetic in both directions:

cost = (input tokens  / 1M x input rate)
     + (output tokens / 1M x output rate)

A token is roughly ¾ of an English word, but that ratio is a rule of thumb rather than a rule — code, JSON, and non-English text tokenize far less efficiently, sometimes at more than one token per character. If you need the real number rather than an estimate, the token counter counts your actual text.

Two things routinely make a real bill exceed the estimate. Conversations resend the whole history on every turn, so a long chat re-bills earlier messages as input again and again. And system prompts, retrieved documents, and tool definitions all count as input tokens even though you never typed them. That is why a per-call estimate and a monthly invoice can differ by an order of magnitude.

Why estimate, then monitor?

A calculator answers “what might this feature cost?” A spend monitor answers “what did we actually spend across OpenAI, Anthropic, Gemini, and OpenRouter?” TryTokka is built for the second question — encrypted keys, daily Scout sync, Sync now, and email when you cross a limit.

Use this page when you are pricing a batch job or comparing GPT-4o mini vs Claude Haiku. When traffic is live, switch to OpenAI spend tracking or the free 7-day trial.