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MaxxMini
MaxxMini

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I Built 25+ Free Developer Tools — Here's the Full Collection

Over the past few weeks, I've been building free developer tools — all client-side, no signup, no ads. Here's the complete collection.

🔐 Security Tools

Password Strength Analyzer

Check password strength with entropy calculation and estimated crack time. Uses zxcvbn algorithm.

Password Generator

Generate secure random passwords with customizable length, character sets, and entropy analysis.

Hash Generator

Generate MD5, SHA-1, SHA-256, SHA-512 hashes instantly. Supports text and file input.

JWT Decoder

Decode and inspect JWT tokens — header, payload, and signature. No data sent to any server.

Dev Security Checklist

Interactive security checklist for web developers. Track your security posture.

AI Security Checklist

Security checklist specifically for AI/ML applications.

🛠️ Developer Utilities

JSON Formatter

Format, validate, and minify JSON with syntax highlighting and error detection.

JSON Error Explainer

Paste broken JSON and get human-readable error explanations with fix suggestions.

Regex Tester

Test regular expressions in real-time with match highlighting and group capture display.

Base64 Encoder/Decoder

Encode and decode Base64 strings. Supports text and file input.

URL Encoder/Decoder

Encode and decode URLs with component breakdown.

Unix Timestamp Converter

Convert between Unix timestamps and human-readable dates. Live clock included.

Cron Expression Parser

Parse and validate cron expressions with next-run predictions and human-readable descriptions.

Markdown Preview

Live markdown preview with GFM support and export options.

Lorem Ipsum Generator

Generate placeholder text by paragraphs, sentences, or words.

🎨 Design Tools

Color Picker

Pick colors with HEX, RGB, HSL conversion and palette generation.

CSS Gradient Generator

Create linear and radial CSS gradients with live preview and copy-ready code.

Box Shadow Generator

Design CSS box shadows with visual controls and instant code output.

📊 SEO & Content

Keyword Mixer

Combine keyword lists to generate all possible variations for SEO campaigns.

QR Code Generator

Generate QR codes for URLs, text, WiFi, and more. Download as PNG or SVG.

Website Audit Tool

Quick website audit — check meta tags, performance hints, and SEO basics.

⏱️ Productivity

Pomodoro Timer

Focused work timer with customizable intervals and break reminders.


Why I Built These

I wanted tools that:

  • Work instantly — no signup, no loading screens
  • Stay private — everything runs in your browser, zero data sent to servers
  • Are actually useful — not demo projects, but tools I use daily

All tools are open source and hosted on GitHub Pages.


🤖 More From Me

🏦 DonFlow — Budget Drift Detector — Plan vs reality budget tracking, 100% in your browser. No backend, no tracking.

🛠️ 18+ Free Dev Tools — Browser-based, no install needed.
🎮 27+ Browser Games — Built with AI agents.
📦 AI Agent Prompt Collection — Templates for your own setup.

If this was useful, drop a ❤️ — it helps more devs find it!

Got questions? Drop them in the comments — I read every one.

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