34 free tools that run entirely in your browser. No sign-up, no install, no tracking. Just open and use.
Built by Developers Digest. All tools are open and free to use.
Estimate token counts for AI models. See approximate costs per request.
Analyze AI prompts for structure, cost, readability, and best practices.
Compare 8 AI coding agents side by side - features, pricing, and context windows.
Format, minify, and validate JSON. Paste messy data, get clean output.
Paste JSON, get TypeScript interfaces, Zod schemas, and Python dataclasses.
Test regular expressions in real time. See matches highlighted as you type.
Compare two blocks of text side by side. See additions, removals, and changes.
Convert cURL commands to JavaScript, Python, Go, and more. Paste and go.
Decode JSON Web Tokens. Inspect header, payload, and signature.
Build cron expressions visually. See next run times in plain English.
Test any API endpoint. Send requests, see response headers, body, timing, and status codes.
Tools built for AI developers - token counting, prompt analysis, agent comparison, and config generation.
Estimate token counts for AI models. See approximate costs per request.
Analyze AI prompts for structure, cost, readability, and best practices.
Compare 8 AI coding agents side by side - features, pricing, and context windows.
Generate a CLAUDE.md config for Claude Code. Pick your stack, get a ready-to-use file.
Generate MCP server configs for Claude Code and Cursor. Pick servers, add keys, download.
Generate .env files with preset templates for Next.js, Vercel AI SDK, Clerk, Supabase, and Stripe.
Parse, format, convert, and validate data. JSON, Base64, URL encoding, HTML entities, and more.
Format, minify, and validate JSON. Paste messy data, get clean output.
Paste JSON, get TypeScript interfaces, Zod schemas, and Python dataclasses.
Encode and decode Base64 strings instantly.
Encode and decode URL components. Handle special characters safely.
Encode and decode HTML entities. Keep special characters safe.
Convert between Unix timestamps and human-readable dates.
Convert between hex, RGB, and HSL color formats with a live preview swatch.
Convert between px, rem, em, and viewport units.
Format code, test regex, compare text, generate snippets, and analyze content.
Test regular expressions in real time. See matches highlighted as you type.
Compare two blocks of text side by side. See additions, removals, and changes.
Format, beautify, and minify SQL queries. Uppercase keywords, indent subqueries.
Convert cURL commands to JavaScript, Python, Go, and more. Paste and go.
Write markdown on the left, see rendered HTML on the right. Live preview.
Convert between camelCase, snake_case, kebab-case, and more.
Count words, characters, sentences, and more. Analyze any text.
Generate placeholder text. Paragraphs, sentences, or words.
Beautiful code snippets with syntax highlighting. Pick a theme and language.
Decode tokens, generate hashes, calculate permissions.
Decode JSON Web Tokens. Inspect header, payload, and signature.
Generate cryptographic hashes. SHA-256, SHA-384, SHA-512, and SHA-1.
Generate unique identifiers. Click to create, click to copy.
Calculate Unix file permissions. Convert between numeric and symbolic notation.
Build cron expressions, generate config files, test APIs, and analyze dependencies.
Build cron expressions visually. See next run times in plain English.
Test any API endpoint. Send requests, see response headers, body, timing, and status codes.
Generate .gitignore files from preset templates. Combine, customize, and download.
Generate meta tags and OG tags with live Google, Twitter, and Facebook previews.
Paste your package.json and get instant analysis. Detect stack, check health, list dependencies.
Create tweets, preview designs, explore the design system.
| # | Tool | Description | Price |
|---|---|---|---|
| 1 | Token Counter | Estimate token counts for AI models. See approximate costs per request. | Free |
| 2 | Prompt Tester | Analyze AI prompts for structure, cost, readability, and best practices. | Free |
| 3 | Agent Compare | Compare 8 AI coding agents side by side - features, pricing, and context windows. | Free |
| 4 | CLAUDE.md Generator | Generate a CLAUDE.md config for Claude Code. Pick your stack, get a ready-to-use file. | Free |
| 5 | MCP Config Generator | Generate MCP server configs for Claude Code and Cursor. Pick servers, add keys, download. | Free |
| 6 | .env Generator | Generate .env files with preset templates for Next.js, Vercel AI SDK, Clerk, Supabase, and Stripe. | Free |
| 7 | JSON Formatter | Format, minify, and validate JSON. Paste messy data, get clean output. | Free |
| 8 | JSON to TypeScript | Paste JSON, get TypeScript interfaces, Zod schemas, and Python dataclasses. | Free |
| 9 | Base64 Encoder | Encode and decode Base64 strings instantly. | Free |
| 10 | URL Encoder | Encode and decode URL components. Handle special characters safely. | Free |
| 11 | HTML Entities | Encode and decode HTML entities. Keep special characters safe. | Free |
| 12 | Epoch Converter | Convert between Unix timestamps and human-readable dates. | Free |
| 13 | Color Converter | Convert between hex, RGB, and HSL color formats with a live preview swatch. | Free |
| 14 | CSS Units Converter | Convert between px, rem, em, and viewport units. | Free |
| 15 | Regex Tester | Test regular expressions in real time. See matches highlighted as you type. | Free |
| 16 | Diff Viewer | Compare two blocks of text side by side. See additions, removals, and changes. | Free |
| 17 | SQL Formatter | Format, beautify, and minify SQL queries. Uppercase keywords, indent subqueries. | Free |
| 18 | cURL to Code | Convert cURL commands to JavaScript, Python, Go, and more. Paste and go. | Free |
| 19 | Markdown Preview | Write markdown on the left, see rendered HTML on the right. Live preview. | Free |
| 20 | Case Converter | Convert between camelCase, snake_case, kebab-case, and more. | Free |
| 21 | Text Stats | Count words, characters, sentences, and more. Analyze any text. | Free |
| 22 | Lorem Ipsum Generator | Generate placeholder text. Paragraphs, sentences, or words. | Free |
| 23 | Code Viewer | Beautiful code snippets with syntax highlighting. Pick a theme and language. | Free |
| 24 | JWT Decoder | Decode JSON Web Tokens. Inspect header, payload, and signature. | Free |
| 25 | Hash Generator | Generate cryptographic hashes. SHA-256, SHA-384, SHA-512, and SHA-1. | Free |
| 26 | UUID Generator | Generate unique identifiers. Click to create, click to copy. | Free |
| 27 | Chmod Calculator | Calculate Unix file permissions. Convert between numeric and symbolic notation. | Free |
| 28 | Cron Builder | Build cron expressions visually. See next run times in plain English. | Free |
| 29 | API Tester | Test any API endpoint. Send requests, see response headers, body, timing, and status codes. | Free |
| 30 | .gitignore Generator | Generate .gitignore files from preset templates. Combine, customize, and download. | Free |
| 31 | Meta Tags Generator | Generate meta tags and OG tags with live Google, Twitter, and Facebook previews. | Free |
| 32 | Package Analyzer | Paste your package.json and get instant analysis. Detect stack, check health, list dependencies. | Free |
| 33 | Tweet Viewer | View and create tweets with live preview, code snippets, and image export. | Free |
| 34 | Design System | The complete visual language - colors, typography, buttons, cards, and tokens. | Free |
These browser tools are just the start. Check out the AI coding tools I use daily to build real projects - Claude Code, Cursor, GitHub Copilot, and more.
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