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OpenAI Token Calculator
An OpenAI token calculator combines a model-appropriate token count with that model’s current input and output rates. Calculate the two usage categories separately, add them for one request, and multiply by request volume. The usage reported by the OpenAI API is authoritative for a completed call.
Choose the model before counting
OpenAI models do not all use the same encoding. A useful calculation starts with the exact model and an encoding that OpenAI documents for that model. A count from a different encoding may not match the model’s request usage.
Keep input and output separate
Input tokens cover content sent to the model, while output tokens cover generated content. OpenAI can publish different prices for these categories, so combining their token totals before applying one rate can produce an incorrect estimate.
Account for the complete request
A pasted prompt may not represent every billed token. System instructions, conversation history, message formatting, tool definitions, cached content, images, audio, and other features can affect recorded usage or introduce separate charges.
Use the matching resource
Use the OpenAI Token Counter to measure visible text with a supported OpenAI encoding. Use the Token Cost Kit homepage to compare token-based costs after selecting models and request volume. Read Counter Token if the phrase needs clarification.