What is a token in the context of AI models?

A token is the basic unit of text that LLMs process. On average, one token is roughly 0.75 words in English. Different models use different tokenizers, so the same text can have slightly different token counts across models.

Why does token counting matter?

Every AI model has a maximum context window measured in tokens. Exceeding this limit causes errors. Token counts also directly determine API costs — models charge per million input and output tokens.

Are these tools accurate for all models?

The tools use model-specific approximations. For exact counts, each provider's official tokenizer (e.g., tiktoken for OpenAI) should be used in production. These tools give reliable estimates for planning and budgeting.

AI Tokens

Count tokens, estimate context usage, and calculate costs across leading AI models. Essential tools for developers building with LLMs who need to stay within context limits and manage API budgets.

BCHAI Batch Cost CalculatorNEW

Calculate total AI API costs across multiple models and request volumes.

CTXAI Context Window CalculatorHOT

Check if your prompts fit within any AI model context window.

CSTAI API Cost CalculatorHOT

Estimate AI API costs for GPT, Claude, Gemini, and LLaMA.

TKNAI Token CounterHOT

Count tokens for GPT, Claude, Gemini, and LLaMA models.

DIFAI Token DiffNEW

Compare token counts between two text versions for any AI model.

VIZAI Tokenizer VisualizerNEW

Visualize how AI models split text into tokens with color coding.

CLDClaude Context Window CalculatorHOT

Calculate token usage against Claude 200K context windows.

CLDClaude API Cost CalculatorHOT

Calculate Anthropic Claude API costs for Sonnet, Opus, and Haiku.

CLTClaude Token CounterHOT

Count tokens for Claude 3.5 Sonnet, Opus, and Haiku models.

GEMGemini Context CalculatorNEW

Calculate token usage against Gemini 1M and 2M context windows.

GEMGemini API Cost CalculatorNEW

Calculate Google Gemini API costs for 1.5 Pro, Flash, and 1.0 Pro.

GEMGemini Token CounterNEW

Count tokens for Gemini 1.5 Pro, Flash, and Gemini 1.0 Pro models.

LLMLLaMA Context CalculatorNEW

Calculate token usage for LLaMA 3.1 models with 128K context.

LLMLLaMA Inference Cost CalculatorNEW

Estimate LLaMA 3.1 API costs on hosted inference providers.

LMALLaMA Token CounterNEW

Count tokens for LLaMA 3.1 405B, 70B, 8B, and LLaMA 3.2 models.

GPTOpenAI Context Window CalculatorHOT

Check if your prompts fit within GPT-4o and GPT-3.5 context windows.

GPTOpenAI API Cost CalculatorHOT

Calculate GPT-4o, GPT-4 Turbo, and GPT-3.5 API costs.

GPTOpenAI Token CounterHOT

Count tokens for GPT-4o, GPT-4 Turbo, and GPT-3.5 models.

FAQ

What is a token in the context of AI models?: A token is the basic unit of text that LLMs process. On average, one token is roughly 0.75 words in English. Different models use different tokenizers, so the same text can have slightly different token counts across models.
Why does token counting matter?: Every AI model has a maximum context window measured in tokens. Exceeding this limit causes errors. Token counts also directly determine API costs — models charge per million input and output tokens.
Are these tools accurate for all models?: The tools use model-specific approximations. For exact counts, each provider's official tokenizer (e.g., tiktoken for OpenAI) should be used in production. These tools give reliable estimates for planning and budgeting.

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