AI/LLM Token Cost Calculator
AI/LLM Token Cost Calculator
Paste a sample of text (like a typical prompt) to estimate its token count using a common approximation, then calculate the total cost of running it across many API requests at a given price per million tokens.
The roughly-1-token-per-4-characters approximation is a well-known rule of thumb for GPT-style tokenizers rather than an exact count from any specific model's real tokenizer, so treat the estimate as a planning figure rather than a billing-accurate number. It's still useful for the thing it's built for: sketching out the likely monthly cost of an AI feature before committing to it, comparing pricing across providers, or sanity-checking whether a prompt is unexpectedly bloated before it goes into production at scale. Everything runs locally in your browser — your sample text is never sent to a server.
- Token estimate formula: roughly 1 token per 4 characters of English text — a widely used approximation for GPT-style tokenizers, not an exact count from any specific model's real tokenizer.
- Runs entirely in your browser: your sample text is analyzed locally using JavaScript and is never sent to a server.
- Pricing varies by model and provider: enter your specific model's price per million tokens (check your AI provider's pricing page) — input and output tokens are often priced differently, so this estimates one side at a time.
Why is this only an estimate and not an exact token count?
Real tokenizers split text into subword pieces based on a trained vocabulary, which varies by model and language — the ~4 characters/token rule is a good rough estimate for English but can be off for other languages or unusual text.
How do I estimate cost for both input and output tokens?
Run this calculator twice — once with your input price and prompt text, once with your output price and an estimated response length — then add the two costs together.
AI/LLM Token Cost Calculator
Paste a sample of text (like a typical prompt) to estimate its token count using a common approximation, then calculate the total cost of running it across many API requests at a given price per million tokens.
The roughly-1-token-per-4-characters approximation is a well-known rule of thumb for GPT-style tokenizers rather than an exact count from any specific model's real tokenizer, so treat the estimate as a planning figure rather than a billing-accurate number. It's still useful for the thing it's built for: sketching out the likely monthly cost of an AI feature before committing to it, comparing pricing across providers, or sanity-checking whether a prompt is unexpectedly bloated before it goes into production at scale. Everything runs locally in your browser — your sample text is never sent to a server.
- Token estimate formula: roughly 1 token per 4 characters of English text — a widely used approximation for GPT-style tokenizers, not an exact count from any specific model's real tokenizer.
- Runs entirely in your browser: your sample text is analyzed locally using JavaScript and is never sent to a server.
- Pricing varies by model and provider: enter your specific model's price per million tokens (check your AI provider's pricing page) — input and output tokens are often priced differently, so this estimates one side at a time.
Why is this only an estimate and not an exact token count?
Real tokenizers split text into subword pieces based on a trained vocabulary, which varies by model and language — the ~4 characters/token rule is a good rough estimate for English but can be off for other languages or unusual text.
How do I estimate cost for both input and output tokens?
Run this calculator twice — once with your input price and prompt text, once with your output price and an estimated response length — then add the two costs together.