Stack Online Tools – Developer Utilities — stackonlinetools.com

Stack Online Tools is the ultimate all-in-one productivity and developer toolkit for Firefox. Stop switching between sites or loading multiple add-ons — access 30+ essential online tools, text utilities, and developer helpers right from your browser.

Built for developers, content creators, digital marketers, SEO professionals, and everyday users, this extension speeds up workflows with fast, lightweight, and privacy-first utilities that run locally when possible.

✔ What You Get

Developer & Code Utilities

• JSON Formatter & Validator – instant formatting, beautification, and error checking
• JSON ↔ YAML Converter
• Base64 Encode/Decode
• URL Encode/Decode
• HTML, CSS & JS Minifiers
• Markdown ↔ HTML Converter
• Robots.txt Generator for SEO and crawler structuring

These tools make Stack Online Tools a top choice for developer tools, programmer utilities, and code formatters in Firefox.

Text & Content Utilities

• Case Converter (uppercase, lower, title, camel, snake, kebab)
• Word & Character Counter
• URL Slug Generator
• Line Counter & List Randomizer
• Text Repeater
• Text Reverser
• Remove Duplicate Lines

Essential for writers, bloggers, SEO editors, and anyone optimizing content.

Security & Password Tools

• Strong Password Generator (custom options)
• Password Strength Checker

Perfect for web developers, admins, and safe credential creation.

Image & File Tools

• PNG ↔ JPG Converter
• PDF ↔ JPG Converter (secure web tool)

Quick Calculators & Generators

• Age Calculator
• Percentage Calculator
• Random Name Generator
• Random Address Generator

Key Benefits

✔ All-in-one productivity tools & utilities
✔ Fast, lightweight, and user-friendly
✔ Privacy-first — tools run locally
✔ No account, registration, or tracking
✔ Replaces multiple single-purpose add-ons

Stack Online Tools supports nearly every common workflow, from text conversions and data formatting to developer operations, making it one of the most versatile Firefox add-ons available.

Who This Is For

• Developers & engineers
• SEO specialists & marketers
• Writers & editors
• Designers & web admins
• Students & everyday users