How accurate is the token counter? What's the difference between estimation and exact counting?

This calculator uses two modes: (1) **Exact mode** via OpenAI's official `tiktoken` library with `o200k_base` encoding — provides 99%+ accuracy matching actual API tokenization for all OpenAI models (GPT-5.5, GPT-5.4, GPT-4o series). (2) **Fallback estimation mode** for non-OpenAI models or if tiktoken fails — uses heuristic algorithms accurate within ±10-15%. The UI shows which mode is active: 'Using tiktoken (exact)' or 'Estimating'. For production-critical applications requiring billing precision, always use the exact mode with OpenAI models.

What is the context window progress bar and how should I interpret it?

The context usage bar visualizes what percentage of the model's total context window your input + output tokens will consume. **Green ( 80%)**: Danger — near capacity, high risk of truncation errors. Each model has different limits (e.g., GPT-5.5 Pro: 1.05M tokens, Claude Opus 4.7: 1M tokens, DeepSeek V4: 1.05M tokens). Use this to prevent failed API calls before they happen.

What is cached input pricing and when should I use it?

Cached input pricing (available for OpenAI models) gives you **50% discount on input tokens** when the model has previously processed identical or similar prompts. This is automatic in production when you use the same system prompt repeatedly, call the same function many times, or send documents that were already processed earlier in the conversation. Toggle the checkbox to see your potential savings — for a chatbot sending a 2000-token system prompt 1000 times/day, this can reduce monthly input costs from $1,800 to $900 with GPT-5.5 Pro.

Why do Chinese characters use more tokens than English? How does the calculator handle mixed-language text?

Most LLM tokenizers (GPT, Claude, Gemini) are trained primarily on English where ~4 characters = 1 token. CJK characters (Chinese/Japanese/Korean) are less common in training data, requiring 1.5-2 tokens per character. This means 100 Chinese characters ≈ 150-200 tokens vs 100 English characters ≈ 25 tokens. The calculator handles mixed-language text by detecting character types and applying appropriate algorithms: uses tiktoken's exact BPE for Latin/CJK mixed text, with special handling for Chinese punctuation and whitespace. This ensures accurate counts even for bilingual prompts like '请分析这个API endpoint: /api/v1/users'.

What are the use-case presets and how do they help?

The 8 presets represent common AI application patterns with research-backed output/input ratios: **Chat** (0.3× — short responses), **RAG** (0.25× — concise answers from docs), **Content Generation** (1.0× — long-form writing), **Code Assistant** (0.8× — code + explanations), **Summarization** (0.2× — condensed summaries), **Translation** (1.2× — usually longer than source), **Data Analysis** (0.5× — insights + charts description), **Custom** (manual control). When you select a preset, it auto-fills typical output token counts and batch estimate parameters based on real-world data from thousands of API calls. This eliminates guesswork when planning budgets.

How do I estimate my monthly API costs accurately?

Use the **Batch Estimate section** at the bottom with these steps: (1) Select your use-case preset to auto-fill realistic averages, (2) Enter expected daily requests (start conservative — most products overestimate initially), (3) Review the auto-calculated input/output token averages (adjust if your use case differs), (4) Check daily/monthly/yearly projections instantly. **Pro tip**: Run estimates for multiple models side-by-side — switching from GPT-5.5 Pro ($30/$180 per 1M) to DeepSeek V4 Flash ($0.098/$0.197 per 1M) can reduce costs 300× for similar quality on many tasks. Always add 20% buffer for unexpected usage spikes.

Which model should I choose for cost efficiency in 2026?

For **2026's competitive landscape**: **Budget tier** (simple tasks): DeepSeek V4 Flash ($0.098/$0.197), Qwen 3.5-Flash ($0.065/$0.26), Llama 4 Scout ($0.08/$0.30) — excellent for classification, extraction, short answers. **Mid-tier** (balanced): GPT-5.4 Mini ($0.75/$4.5), Claude Haiku 4.5 ($1/$5), Gemini 3 Flash ($0.5/$3) — good for coding assistance, content drafting, RAG. **Flagship** (complex reasoning): GPT-5.5 Pro ($30/$180), Claude Opus 4.7 ($30/$150), Gemini 3.5 Flash ($1.5/$9) — necessary for multi-step reasoning, architecture design, creative writing. **Chinese language optimization**: DeepSeek V4 Pro, Qwen 3.6 Max, GLM-5.1 outperform Western models on Chinese tasks at lower cost. Use the model switcher to compare exact costs for your specific prompt.

Are the prices shown current? How often are they updated?

**Pricing updates**: We monitor official provider pricing pages (OpenAI, Anthropic, Google AI, DeepSeek, Qwen, etc.) and update our database regularly to reflect the latest rates as of June 2026. However, providers frequently run promotional pricing or introduce new models — always verify on official sites before committing to large-scale deployments. The tool shows 35 models covering the full spectrum from free tier to $30 per 1M input tokens.

Does this work for fine-tuned models or custom endpoints?

**Fine-tuned models**: Yes — they inherit the parent model's tokenizer, so token counts remain accurate. However, fine-tuned inference pricing varies wildly (some charge per GPU-hour, not per-token). Use the token counter for volume planning, but check your provider's specific fine-tuning docs for cost projection. **Custom/local models**: The tiktoken exact mode works for any OpenAI-compatible model. For Llama, Mistral, Qwen, or other open-weight models running locally, use estimation mode (±15% accuracy) since their tokenizers differ slightly from OpenAI's. **Enterprise APIs (Azure, AWS Bedrock, Vertex)**: Token counts are identical, but enterprise pricing may include volume discounts not shown here — contact your account rep for accurate enterprise rates.

Is my text data secure? Does anything get sent externally?

**100% client-side processing** — All calculations happen entirely in your browser via JavaScript. Your text never leaves your device: no network transmission after initial page load, no server-side processing, no logging, no storage anywhere. Verify this yourself: disconnect from internet after loading the page — the calculator continues working fully offline including tiktoken tokenization. We take privacy seriously because users paste sensitive content: proprietary code, business strategies, confidential documents, customer data, authentication keys. The only external call is loading the tiktoken WASM library (~200KB one-time from CDN) — this does not transmit your text.

What's the difference between this tool and the model-specific pages (/token-calculator/gpt-5-5-pro, etc.)?

**Functionally identical** — All pages support the full feature set (precise token counting, context window visualization, presets, batch estimation). Model-specific pages (e.g., /token-calculator/gpt-5-5-pro) auto-select that model and show optimized tips for that particular model. Use the main tool for daily use; if you searched for a specific model (like 'GPT-5.5 Pro token calculator'), you can go directly to its dedicated page.

AI Token Calculator — Count Tokens & Estimate Costs for GPT-5.5, Claude Opus 4.7, DeepSeek V4

Input text

Token count

Characters

Words

Select model

Provider:OpenAI

Context window:1.1M tokens

Max output:128.0K tokens

Price per 1M tokens:In: $30 / Out: $180

Cached In:$15 (50% off)

Select use case preset

Output tokens

Use cached input pricing (50% off)

Batch estimate

Requests per day

Avg input tokens

Avg output tokens

Daily cost

$10.50

Monthly cost (30 days)

$315.00

Yearly cost (365 days)

$3832.50

AI Token Calculator — Count Tokens & Estimate Costs for GPT-5.5, Claude Opus 4.7, DeepSeek V4

Free online AI token calculator with OpenAI tiktoken precision (99%+ accuracy). Count exact tokens and estimate API costs for GPT-5.5 Pro, Claude Opus 4.7, Gemini 3.5 Flash, DeepSeek V4 Pro/Flash, Qwen 3.6 Max, and 32 LLM models. Features: context window visualization, cached input pricing (50% off), 8 use-case presets (Chat/RAG/Code), batch cost projection, multi-model comparison. Supports English, Chinese, Japanese, Korean, and mixed-language text. All calculations run locally — no data uploaded.

Features

✓Precise token counting using OpenAI's official tiktoken library (o200k_base encoding) — 99%+ accuracy matching actual API tokenization for GPT-5.5, GPT-5.4, and all OpenAI models

✓Real-time context window visualization with color-coded progress bar — green (<50%), yellow (50-80%), red (>80%) — shows exact usage percentage and remaining tokens

✓Cached input pricing support (50% discount) for OpenAI models — toggle to see savings when using prompt caching or repeated system prompts in production

✓8 use-case presets (Chat, RAG, Content Generation, Code Assistant, Summarization, Translation, Data Analysis) with auto-calculated output ratios

✓Multi-model support for 32 LLMs including GPT-5.5 Pro, Claude Opus 4.7, Gemini 3.5 Flash, DeepSeek V4 Pro/Flash, Qwen 3.6 Max, GLM-5.1, Kimi K2.5, MiniMax M3, MiMo V2.5 Pro

✓Input/output token separation with independent cost calculation for transparent billing structure understanding

✓Instant cost estimation per API call with cached input pricing option displayed separately for production budgeting

✓Batch cost projection calculator — estimate daily, monthly (30-day), and yearly (365-day) API expenses based on expected request volume and use case

✓Model comparison dropdown with context window limits, max output tokens, cached pricing support, and provider information displayed for each selection

✓One-click copy functionality for token counts, cost estimates, and batch projections to share with team members or include in documentation

✓Comprehensive model metadata display including provider name, context window size, max output tokens, cached input pricing, and per-million-token pricing

✓Character and word count statistics alongside exact token count for complete text analysis in one place

✓Asynchronous tiktoken initialization with 300ms debounce — smooth UX without blocking UI during precise token calculation

✓Automatic fallback to heuristic estimation if tiktoken fails — ensures tool always works even in constrained environments

✓No data transmission — all calculations run locally in your browser using JavaScript, ensuring privacy for sensitive prompts and code

✓Smart currency formatting with dynamic decimal places (shows up to 6 decimals for tiny amounts, 2 for larger values)

How to Use

1Paste or type your text into the input area on the left — the calculator uses tiktoken for exact token counting (shows 'Using tiktoken (exact)' when ready). For Chinese text, each character typically uses 1-2 tokens.

2Select your target AI model from the dropdown menu (default is GPT-5.5 Pro). Model pricing, context window, and limits appear automatically below. OpenAI models show cached input pricing option.

3View real-time statistics: exact token count (via tiktoken), character count, and word count appear in the stat cards. A context usage progress bar shows how much of the model's context window you're using.

4Choose a use-case preset from the dropdown (Chat, RAG, Code Assistant, etc.) or select 'Custom' — this auto-calculates typical output token ratios based on real-world patterns.

5Set or adjust output tokens manually if needed — the preset provides a smart default based on your selected use case and input length.

6Enable 'Use cached input pricing' checkbox (for OpenAI models) to see 50% cost reduction on input tokens — critical for production apps with repeated system prompts.

7Review the cost breakdown showing input cost, cached input cost (if enabled), output cost, and total cost per API call. Click any amount to copy it.

8Monitor the context usage bar: green means safe (<50%), yellow means caution (50-80%), red means danger (>80%) — helps avoid truncation errors before API calls.

9Use the Batch Estimate section at the bottom to project daily/monthly/yearly costs by entering expected request volume — presets auto-fill average token usage for your chosen scenario.

10Switch between models anytime to compare costs across providers — the tool recalculates everything instantly including context usage and cached pricing availability.

Frequently Asked Questions