Sub-word tokenizers split punctuation, escaped quotes, and indentation whitespace into separate token IDs, causing formatted JSON to consume 2x more tokens than compact formats.
LLM Token Counter & API Cost Estimator
Measure exact token counts for prompts, JSON payloads, and code—and compare API pricing across Gemini, GPT, and Claude.
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Convert JSON to TOON (Token-Oriented Object Notation)
Compress verbose JSON payloads into LLM-friendly Token-Oriented Object Notation to cut prompt token usage by up to 60%.
Convert JSON to TypeScript & Zod Schemas
Generate clean TypeScript interfaces, type aliases, and runtime Zod validation schemas (`z.object`) from any JSON payload.
Online Semantic JSON Diff & Comparator
Compare two JSON payloads semantically—ignoring key order and formatting—to spot added, removed, and modified values.
Key Capabilities
Engine Features & Specifications
Real-Time Tokenization in Your Browser
Paste any system prompt, RAG document chunk, or JSON response to see total tokens, character count, word count, and token-to-word ratios immediately.
Compare Per-Request & Monthly API Costs Across Models
Adjust the daily request multiplier (e.g., 1,000 or 100,000 calls/day) to compare exact input and output costs across flagship and flash/mini tiers.
Optimize Structured Prompts Before Deploying
Test how minifying JSON or switching to TOON/YAML reduces your per-request token footprint in real time.
Common Inquiries
Frequently Asked Questions
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