Developer Tools

Format JSON, decode JWT, generate UUIDs & hashes, test regex, convert bases — your client-side dev swiss knife.

59 tools 100% client-side
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JSON Formatter

Beautify, minify and validate JSON — 100% in your browser.

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Base64 Encode / Decode

Convert text to and from Base64 — Unicode-safe, no uploads.

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URL Encode / Decode

Percent-encode or decode URLs and query strings — locally.

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JWT Decoder

Inspect JWT header and payload — no signature verification.

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UUID Generator

Generate cryptographically-secure UUID v4s — bulk & instant.

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Hash Generator

Compute SHA-1, SHA-256 and SHA-512 hashes — locally.

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Number Base Converter

Convert between binary, octal, decimal & hex — BigInt-powered.

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Regex Tester

Test JavaScript regex with live match highlighting & groups.

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Markdown Preview

Write Markdown and see the rendered HTML live — side by side.

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JSON to CSV

Convert an array of JSON objects into clean CSV — locally.

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JSON ↔ YAML Converter

Convert JSON to YAML and YAML back to JSON — no libraries.

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HTML Entities Encode / Decode

Escape & unescape HTML entities — live, no uploads.

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CSS Minifier & Beautifier

Compress or re-indent CSS — instantly, locally.

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JS Minifier & Beautifier

A conservative JS formatter — strip // comments, dedent, beautify.

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SQL Formatter

Beautify SQL with uppercase keywords & sensible line breaks.

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Cron Expression Parser

Explain a 5-field cron expression and compute its next 5 runs.

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HMAC Generator

Compute HMAC-SHA-256/384/512 signatures — locally.

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Text ↔ Binary Converter

Convert text to binary and back — UTF-8 safe.

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HTTP Status Codes Reference

Searchable reference of 60+ HTTP status codes — click to copy.

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.gitignore Generator

Build a project-specific .gitignore in seconds — local, downloadable.

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README Generator

Generate a polished README.md from a few inputs — copy or download.

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Random Number Generator

Cryptographically-secure random integers — unbiased, local.

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Username Generator

Generate memorable usernames — adjective+noun, leetspeak, full names.

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CSV ↔ JSON Converter

Convert CSV to JSON and back — RFC 4180 compliant, no uploads.

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YAML ↔ JSON Converter

Convert YAML to JSON and back — pure JS, no dependencies.

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XML Formatter & Minifier

Beautify or minify XML — handles attributes, CDATA, comments.

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JSON to TypeScript

Infer a TypeScript interface from any JSON sample.

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HTML to Markdown Converter

Convert HTML to clean Markdown via DOMParser — no regex hacks.

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String Escape / Unescape

Escape strings for JS, HTML, CSS, JSON, regex, URL and shell.

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JSON Schema Generator

Infer a draft-07 JSON Schema from a sample JSON object.

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Code Formatter

Beautify or minify JSON, CSS, HTML, SQL and XML in one tool.

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HTTP Headers Decoder

Parse and annotate raw HTTP headers — 60+ known headers.

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JSONL Formatter

Beautify, minify and convert JSON Lines — log-friendly.

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Dockerfile Generator

Generate multi-stage Dockerfiles for Node, Python, Go, Rust.

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.htaccess Generator

Build Apache .htaccess rules — HTTPS, redirects, caching, more.

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CSP Builder

Build a Content-Security-Policy header with a clean UI.

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bcrypt Hash Generator

Generate a bcrypt-format password hash — local, no uploads.

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SSH Key Generator

Generate an RSA keypair via Web Crypto — SPKI / PKCS#8 PEM.

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IP Subnet Calculator

Compute network, broadcast, mask and host range for IPv4 / IPv6.

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Email Validator

RFC 5322 format check — no DNS lookup, fully client-side.

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Credit Card Validator

Luhn checksum + card type detection — 100% private.

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ISBN Validator

Validate ISBN-10 and ISBN-13 checksums — mod 11 / mod 10.

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IBAN Validator

Mod-97 checksum for International Bank Account Numbers.

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chmod Calculator

Convert between octal (755) and symbolic (rwxr-xr-x) permissions.

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curl Command Builder

Build a curl command from a friendly UI — shell-safe quoting.

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nginx Config Generator

Generate nginx server blocks — static, SPA, proxy, PHP-FPM, HTTPS.

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Keyboard Shortcut Reference

Searchable reference of 70+ shortcuts across Windows, macOS, browser, VS Code.

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HTML Heading Validator

Check h1–h6 structure for SEO — skips, multiple h1s, empty headings.

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llms.txt Generator

Generate an llms.txt file to guide LLMs to your docs.

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Truth Table Generator

Generate a truth table for any boolean expression.

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Fake Data Generator

Generate fake JSON, CSV or SQL records for testing — 18 fields.

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My IP Address

See your public IPv4, IPv6 and WebRTC-discovered IP.

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Viewport Inspector

Live viewport size, DPR, orientation and Tailwind breakpoints.

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JSONPath Tester

Evaluate JSONPath expressions against JSON — pure JS.

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JSON-LD Builder

Build Schema.org JSON-LD snippets for rich results.

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TOML ↔ JSON Converter

Convert TOML to JSON and back — pure JS, no deps.

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X.509 Certificate Decoder

Decode a PEM X.509 certificate — subject, issuer, validity.

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Script Generator

Pre-built bash, PowerShell, Python, Node and git scripts.

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YAML Formatter

Beautify or minify YAML — pure JS, no dependencies.

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