TokenCalculator.dev

TokenCalculator.dev is a privacy-first, 100% browser-based LLM token counter and API cost estimator designed for AI engineers, developers, and product teams. 

Unlike traditional counters that transmit prompts to third-party servers, TokenCalculator executes text parsing, image processing, and token calculation locally in your browser.

Key Features:

• Multimodal Ingestion: Count tokens and estimate costs from text, local documents (PDF, DOCX, and code in 20+ languages up to 12 MB), and images (PNG, JPEG, WebP, GIF).

• Multi-Model Comparison: Compare live token counts, context-window fit, and real-time input costs across OpenAI, Anthropic Claude, Google Gemini, and DeepSeek.

• Calibrated Accuracy: Combines exact client-side o200k_base BPE tokenization with provider-calibrated projections and official vision patch/tile formulas.

• 100% Client-Side Privacy: Zero prompt logging, zero server uploads, and no external tracking.