Token Counter
Count tokens for GPT, Claude, and Gemini
Open toolUtilZilla / The collection
AI utilities.
Plan your LLM work with token counts, cost estimates, context budgets, and configuration helpers. These are local utilities; they do not call an AI service.
AI API Cost Calculator
Estimate LLM API costs from token counts
Open toolContext Window Calculator
Check if your text fits a model's context window
Open toolJSON Schema Validator
Validate JSON against a schema
Open toolllms.txt Generator
Create an AI-readable site summary file
Open toolEmbedding Cosine Similarity Calculator
Compare embedding vectors by similarity
Open toolMCP Server Risk Checker
Spot risky MCP server configs before installing
Open toolAI Agent Config Converter
Convert one agent prompt into 5 platform formats
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