OpenAI tokenizer
OpenAI Token Calculator
Count prompt tokens with OpenAI tiktoken-compatible encodings and estimate input, output, per-request, and monthly API cost.
Count OpenAI tokens with tiktoken encodings
[]Use OpenAI-style encodings
Switch between o200k_base and cl100k_base for modern OpenAI text workloads.
Estimate API spend
Combine counted input tokens with expected output length and request volume.
Runs in the browser
The tokenizer and cost math run locally in your browser. The page does not upload prompt text.
When to use this OpenAI token calculator
Use this page when you need OpenAI-oriented token counts for prompts, document chunks, system messages, examples, or other raw text before estimating API spend.
The cost estimate uses input tokens * input price + expected output tokens * output price, then multiplies that request cost by monthly request volume.
| Need | Recommended page | Reason |
|---|---|---|
| OpenAI API cost | OpenAI API Cost Calculator | Uses counted or estimated tokens to model production API spend. |
| OpenAI token counting | OpenAI Token Calculator | Uses tiktoken-compatible encodings for raw text. |
| Cross-provider estimate | Token Counter | Works across OpenAI, Claude, and Gemini-style planning. |
| Monthly LLM budget | LLM Cost Calculator | Models users, request volume, input tokens, output tokens, and cached input. |
FAQ
Is this the same as the OpenAI API usage number?
Not always. The raw text token count should match the selected encoding for text, but API usage can include chat formatting, tool call, or response-format overhead.
Which encoding should I choose?
Use o200k_base for newer OpenAI-style workloads and cl100k_base when comparing against older GPT-4/GPT-3.5-era examples.
References
Pricing data was last checked on 2026-07-02. Verify pricing and tokenizer behavior against official OpenAI sources before final budgeting.