⚡ 6 Free Dev Tools

Developer Tools
That Just Work

Fast, browser-based utilities for everyday developer tasks. No sign-up, no tracking — everything runs locally in your browser.

// tools

🔐 Base64 Encoder / Decoder Encode strings or binary data to Base64 and decode back. Supports URL-safe variant.

btoa()atob()RFC 4648

Open tool → 🕐 Unix Timestamp Converter Convert Unix timestamps to readable dates and vice versa. Shows code examples in 5 languages.

UnixISO 8601UTC

Open tool → 📋 JSON Formatter & Validator Beautify, minify, and validate JSON. Syntax error highlighting with line and column info.

BeautifyMinifyValidate

Open tool → 🔑 Password Generator Generate cryptographically secure random passwords. Customize length and character sets.

crypto.randomCSPRNG

Open tool → 🔗 URL Encoder / Decoder Percent-encode URLs and decode them back. Supports both full URL and component encoding.

encodeURI%20RFC 3986

Open tool → 🏷️ HTML Entity Encoder Encode special characters to HTML entities and decode them back. Essential for XSS prevention.

&<XSS safe

Open tool →

No tools match ""

Runs 100% in your browser

Zero data sent to servers

No sign-up required

Always free

// why developertools.app?

Built by developers, for developers. Every tool does one thing well and runs entirely in your browser.

⚡ Instant

No round-trips to a server. Results appear as you type — even on a plane with no internet.

🔒 Private

Your API keys, tokens, and passwords never leave your machine. Everything runs in your browser's JS engine.

📖 Documented

Every tool includes code examples in multiple languages, so you can replicate the logic in your own apps.

// faq

Are these tools really free?

Yes, completely free. The site is ad-supported so we can keep all tools free without paywalls, accounts, or usage limits.

Is my data safe to paste here?

Absolutely. All tools run entirely in your browser using JavaScript. Nothing is transmitted to any server, logged, or stored. You can safely paste API keys, tokens, private config values, and sensitive data.

Do the tools work offline?

Yes. Once the page has loaded, all tools function without an internet connection since all processing happens locally in your browser.

Can I suggest a new tool?

Yes — email hello@developertools.app with your suggestion. Tools get added based on demand and usefulness.