Token Count & Cost Estimator
Exact token counting using cl100k_base tokenizer (GPT-4 standard). Estimate costs for OpenAI, Anthropic, and Google models.
100% Private & Secure✓ Client-Side Counting✓ No Data Sent to Server✓ Offline Ready
Your data is processed locally in your browser and is never uploaded to any server.
Tokens
0
Characters
0
Input Cost
$0.000000
Output Cost
$0.000000
About Model Pricing
Cost estimates are based on current API pricing per 1M tokens. "Input Cost" is essentially the cost to process your prompt, while "Output Cost" is the projected cost if the model generated the exact same amount of text as a response.
How It Works — Exact Token Counting
How It Works — Exact Token Counting
Unlike other estimators that guess based on word count, this tool uses the actual **cl100k_base tokenizer** (via js-tiktoken) used by OpenAI's GPT-4 and o1 models. This ensures your token counts are 100% accurate for these models.
- Precision: Uses standard industry tokenizers, not rough estimates
- Visuals: See exactly how the model splits your text into tokens
- Privacy: All processing happens locally in your browser
- File Support: Upload text files directly to count large documents
Why Accuracy Matters
Why Accuracy Matters
API costs can accumulate quickly. A 10% error in token estimation for a large batch job can cost hundreds of dollars. By using the exact tokenizer, you can predict your expenses with precision and optimize your prompts to fit within context windows.
- Budget Control: Know your exact API spend before running requests
- Context Optimization: Fit maximum context without hitting token limits
- Prompt Engineering: Visualize how slight wording changes affect token usage
Supported Models & Pricing
Supported Models & Pricing
- OpenAI o1 Series: Support for o1-preview and o1-mini reasoning models
- GPT-4o & Turbo: Accurate counts for the latest flagship models
- Anthropic Claude: Estimates for Claude 3.5 Sonnet and Opus
- Google Gemini: Cost calculations for Gemini 1.5 Pro and Flash
Glossary
- cl100k_base
- The specific tokenizer used by GPT-4, GPT-4o, and o1 models. It handles text compression more efficiently than older tokenizers.
- Context Window
- The limit on how much text a model can process at once (e.g., 128k tokens for GPT-4o).
- Input Cost
- The price you pay for the text you send to the model (your prompt).
- Output Cost
- The price for the text the model generates. This is usually more expensive than input tokens.