Anthropic Token Counter

What is an Anthropic Token Counter?

An Anthropic token counter calculates the number of tokens in text for Anthropic's Claude models. Tokens are the units Anthropic uses to measure text length—approximately 4 characters per token. Counting tokens is essential for estimating API costs, managing context windows, and optimizing prompts for Claude models.

Why Count Anthropic Tokens?

Token counting is crucial for Claude API usage:

• Cost Estimation: Estimate API costs before making requests (Anthropic charges per token)
• Context Window Management: Ensure prompts fit within Claude's 200K token context limit
• Prompt Optimization: Reduce token usage to lower costs and improve efficiency
• Budget Planning: Plan API budgets for Claude-based AI projects
• Model Selection: Compare token usage across different Claude models

Common Use Cases

API Cost Estimation

Estimate costs before making Anthropic API requests. Different Claude models have different pricing—Opus costs more than Haiku. Count tokens to predict expenses accurately.

Prompt Optimization

Optimize prompts to reduce token usage. Fewer tokens mean lower costs and faster responses. Use token counting to identify verbose sections and trim unnecessary content.

Context Window Management

Verify prompts fit within Claude's 200K token context window. Claude models support large contexts—token counting helps ensure you don't exceed limits.

Budget Planning

Plan API budgets for Claude-based projects. Calculate token usage for typical workflows to estimate monthly costs and set usage limits.

Model Comparison

Compare token counts across Claude models. Understand how the same prompt tokenizes differently in Opus vs Haiku to choose the right model.

Claude Models Supported

Our counter supports all major Claude models:

• Claude Sonnet 4.5: Most intelligent model, excels at complex tasks and autonomous operations
• Claude Haiku 4.5: Near-frontier performance at 1/3 the cost of Sonnet 4, optimized for speed
• Claude Opus 4: Most capable model with 200K context
• Claude Sonnet 4: Balanced performance and cost
• Claude 3.5 Sonnet: High-performance model
• Claude 3.5 Haiku: Fast and cost-effective
• Claude 3 Opus: Previous generation flagship model
• Claude 3 Sonnet: Previous generation balanced model
• Claude 3 Haiku: Previous generation fast model
• Claude 2.1 & 2.0: Legacy models

How Token Counting Works

Anthropic uses tokenization similar to OpenAI:

• Accurate Counting: Our tool uses accurate tokenization methods
• Real-time Updates: See token count as you type
• Context Window: Shows percentage of 200K context window used

Token Counting Best Practices

• Real-time Counting: Count tokens as you write prompts to stay within limits
• Include System Messages: Count system messages, user messages, and assistant messages
• Estimate Output: Consider output token costs (often more expensive than input)
• Monitor Usage: Track token usage over time to optimize costs
• Model Selection: Choose models based on token limits and pricing

Understanding Token Costs

Anthropic pricing varies by model:

• Claude Sonnet 4.5: $4 per 1M input tokens, $20 per 1M output tokens
• Claude Haiku 4.5: $1 per 1M input tokens, $5 per 1M output tokens
• Claude Opus 4: $15 per 1M input tokens, $45 per 1M output tokens
• Claude Sonnet 4: $3 per 1M input tokens, $15 per 1M output tokens
• Claude 3.5 Haiku: $0.80 per 1M input tokens, $4 per 1M output tokens

Privacy and Security

Our Anthropic Token Counter processes all text entirely in your browser. No text or prompts are sent to our servers, ensuring complete privacy for sensitive prompts and data.

Related Tools

If you need other AI or developer tools, check out:

• OpenAI Token Counter: Count tokens for GPT models
• Llama Token Counter: Count tokens for Llama models
• Regex Tester: Test regular expressions