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AI Token Counter Online — Free LLM Tokenizer for GPT-4o, Claude, Gemini & Llama

AI Token Counter

Count tokens and estimate API costs for major LLMs instantly.

Free online AI token counter. Paste your text or prompt and instantly see token counts for GPT-4o, GPT-4.1, Claude Opus/Sonnet, Llama 3, Gemini 2.5, and Mistral. Compare token counts across all models in a single table. Estimate per-request input/output costs, then project monthly spend for your workload in the AI Cost Calculator. Uses exact BPE tokenization for OpenAI models. Runs entirely in your browser — no data is ever sent to a server.

Keywords: token counter, ai token counter, tiktoken, llm tokens, openai tokens, claude tokens, gpt-4o tokens, token cost, token counter online, count tokens, token estimator, gemini tokens, llama tokens

Tags: tokens, ai, llm, tokenizer, count, estimate

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How to AI Token Counter Online

  1. Paste your text or prompt into the input area on the left.

  2. Select the AI model you want to target (e.g., GPT-4o, Claude 3.5 Sonnet, Gemini 2.5) from the settings panel.

  3. The tool instantly counts the tokens as you type — no need to click any button.

  4. View the precise token count, character count, and word count in the results panel.

  5. See instant estimates for API costs (input and output) based on the current model's pricing.

  6. Click 'Compare all models' or press ⌘⇧A to view a table showing token counts and costs across all supported LLMs simultaneously.

  7. Copy the results or share your prompt via a secure URL.

AI Token Counter Features

  • Real-time token counting: instantly calculates tokens as you type or paste text.

  • Multi-model support: accurate tokenization for OpenAI (GPT-4o, GPT-4, GPT-3.5), Anthropic (Claude 3.5, 3), Google (Gemini 2.5, 1.5), and open-source models (Llama 3, Mistral).

  • API cost estimation: calculates precise input and output costs based on official provider pricing.

  • Model comparison matrix: compares token counts and costs across all models in a single view.

  • Exact BPE tokenization for OpenAI models using tiktoken for precise counts.

  • Granular statistics: displays character count, word count, and token density.

  • Client-side processing: all text is processed locally in your browser for total privacy — no prompts are ever sent to a server.

  • Fast and responsive: handles large prompts seamlessly without lag.

  • Keyboard shortcuts for power users: ⌘⇧A to compare all models, ⌘⇧K to clear input, ⌘⇧C to copy results.

Frequently Asked Questions

What is a token in AI?
A token is a piece of a word used by Large Language Models (LLMs) to process text. Depending on the model, a token can be a single character, a chunk of a word, or an entire word. On average in English, 1 token is approximately 4 characters or 0.75 words.
Is this AI token counter free?
Yes, DevFlow's AI Token Counter is completely free. You can count tokens and estimate costs for any length of text without any limits or subscriptions.
Are my prompts kept private?
Absolutely. All token counting is performed entirely in your browser. Your text and prompts are never sent to any server, ensuring complete data privacy for sensitive information.
Why do different models have different token counts?
Different AI companies use different tokenizers (the algorithms that break text into tokens). For example, OpenAI uses `tiktoken` with specific encoding schemes (like `o200k_base`), while Anthropic and Google use their own custom tokenizers. This is why the same text yields different token counts across models.
How accurate are the cost estimates?
The per-request estimates are based on the official per-million-token pricing from providers like OpenAI, Anthropic, and Google. For projecting monthly spend across many models — including cache tiers and workload volume — use the AI Cost Calculator, which scores every model against your exact workload.
Can I compare costs across different LLMs?
Yes. Use the 'Compare all models' feature to view a side-by-side matrix of token counts and estimated per-request costs for your text. To compare projected monthly spend for a production workload (calls per day, prompt caching, batch discounts), open the AI Cost Calculator with your token counts.
Does this tool work offline?
Yes. Once the page is loaded, the tokenization logic runs locally in your browser via JavaScript or WebAssembly, so you can continue to use the tool even without an internet connection.

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