Free Claude & MCP Developer Tools

Browser-based tools for Claude Code and MCP development. No sign-in, no API keys, no cost.

Claude Token Counter

Estimate token usage for your CLAUDE.md, system prompt, or any text. See context window usage and cost per model — runs entirely in your browser.

Count tokens
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Markdown Validator

Lint your Markdown for broken links, heading hierarchy issues, unclosed code fences, duplicate headings, and style problems. Live preview included.

Validate Markdown

CLAUDE.md Generator

Generate a CLAUDE.md configuration file for your project. Choose your framework, language, and tooling — get a ready-to-use file instantly. No AI, no API key.

Generate CLAUDE.md
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Cursor → CLAUDE.md Converter

Migrating from Cursor AI to Claude Code? Paste your .cursorrules file and get a CLAUDE.md equivalent instantly. Free, browser-based converter.

Convert rules

MCP Config Builder

Generate a claude_desktop_config.json snippet for Claude Desktop. Pick MCP servers from the catalog, fill in your credentials, and copy.

Build config

MCP README Generator

Generate a professional README.md for your MCP server. Fill in tools, env vars, and installation steps — get a complete, formatted README instantly.

Generate README
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Slash Command Generator

Build custom Claude Code slash commands. Fill in the name and instructions — generates a .claude/commands/ file ready to drop into your project.

Build command

.gitignore Generator

Select your stack and get a clean, combined .gitignore in seconds. Supports Node.js, Python, Go, Rust, Docker, macOS, Windows, and more.

Generate .gitignore
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JSON → TypeScript

Paste any JSON object and get fully typed TypeScript interfaces instantly. Handles nested objects, arrays, optional fields, and union types.

Convert JSON

Claude Model Comparison

Compare Claude Haiku 4.5, Sonnet 4.6, and Opus 4.6 side by side. Pricing, context windows, speed, and use cases to help you pick the right model.

Compare models
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System Prompt Builder

Build a structured system prompt for Claude. Set the role, tone, task focus, output format, and constraints — get a ready-to-paste prompt for Claude API or Claude.ai.

Build prompt
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Prompt Token Optimizer

Paste any Claude prompt and instantly see token count, API cost across models, and an optimized version with filler phrases removed. Reduce costs without losing clarity.

Optimize prompt
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Claude API Cost Calculator

Estimate your monthly Anthropic API bill. Enter token usage and request volume — get a cost breakdown across Haiku, Sonnet, and Opus with live comparison.

Calculate cost
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JSON Formatter & Minifier

Format JSON with proper indentation, minify to a single line, or validate syntax. Side-by-side editor with size stats. No data sent to any server.

Format JSON
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Regex Tester

Test and debug regular expressions in real time. Matches are highlighted as you type, with a full match list showing index positions and capture groups. Free, browser-based.

Test regex

All tools run entirely in your browser — no data is sent to any server.