PureDevTools

AI & LLM Tools

Tools for AI developers: token counting, cost calculation, prompt engineering, model comparison, and config generation for Claude, GPT, Gemini, and more — all in your browser, prompts stay private.

16 tools — All free, no sign-up, runs entirely in your browser.

LLM Token Counter

Count tokens for GPT-4, Claude, Gemini, and Llama models with cost estimates.

LLM Cost Calculator

Compare API costs across 17+ AI models. Calculate daily and monthly spend.

AI Model Comparison

Compare 13+ AI models: pricing, context windows, capabilities. Filter by use case.

Context Window Visualizer

Visualize how much of an LLM's context window your prompt fills.

Prompt Diff

Compare two AI prompt versions side by side with inline diff highlighting.

System Prompt Builder

Build structured system prompts with templates for code, writing, and analysis.

Function Calling Schema Builder

Build tool/function calling schemas for OpenAI and Anthropic APIs visually.

SSE Stream Parser

Parse and debug Server-Sent Events streams from AI API responses.

.cursorrules Generator

Generate Cursor AI project config files with framework-specific presets.

CLAUDE.md Generator

Generate Claude Code project instruction files with 8 project type templates.

MCP Config Generator

Generate Model Context Protocol server config for Claude Desktop and Cursor.

AGENTS.md Generator

Generate AGENTS.md files for AI coding agents with role and constraint presets.

AI Response Formatter

Format and clean up AI model responses for better readability.

Structured Output Validator

Validate AI structured output against JSON schemas.

Vibe Coding Prompt Builder

Build effective coding prompts for AI assistants.

Prompt Diff Tool

Compare two prompts side-by-side to see differences.

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