TokenAtlasTokens, not words
AI APIs bill per token, not per word. 1 token ≈ 0.75 English words. A 300-word email is ~400 tokens. Code and non-English languages tokenize less efficiently — sometimes 2–3× more tokens per character.
Input vs output
Every request has an input cost (what you send) and an output cost (what the model generates). Output is almost always 3–5× more expensive per token than input.
Per-model rates
Cheaper models exist for simple tasks. Gemini Flash is ~30× cheaper than GPT-4o per token. Choosing the right model is the highest-leverage cost decision.
Hidden costs
System prompts re-billed each call. Retries on errors. Tool-call overhead. Streaming has no cost effect but matters for UX. None of these show up in marketing pricing pages.
Frequently asked questions
- How do I know my token count?
- Use the provider tokenizer or TokenAtlas's live counter — paste text and see tokens instantly.
- Are there free tiers?
- Google offers a generous Gemini free tier; OpenAI and Anthropic offer trial credits.
- Can I cap my spend?
- Yes — every provider supports monthly budget caps. Always set one.