Introducing DevTools on Stable Numbers

We have launched a new section of Stable Numbers, built for developers called DevTools.

While most of the site focuses on calculators, converters, and finance tools, this new area is designed for people who work with code, design systems, and data every day. It takes the same approach as the rest of Stable Numbers: clean, fast and accurate.

At the moment, the DevTools section includes:

• Colour Contrast Checker – WCAG Compliance
  Check text and background contrast for accessibility, preview combinations, simulate colour blindness and meet WCAG AA or AAA standards.
• CSS Grid System Calculator
  Generate responsive grid layouts with custom columns, gutters and breakpoints. A quick way to get the layout maths right before writing your CSS.
• Custom Stylesheet Generator
  Build lightweight CSS frameworks by selecting only the components you need. Ideal for rapid prototyping or learning how frameworks are structured.
• JWT Debugger
  Decode and inspect JSON Web Tokens directly in your browser. See headers, payloads and claims without relying on external APIs.
• Regex Tester
  Test and debug regular expressions in real time with syntax highlighting and pattern explanations. Supports multiple languages, including JavaScript, PHP and Python.
• SQL Query Builder
  Visually construct SQL queries for SELECT, INSERT, UPDATE and DELETE operations. A simple way to check syntax or build quick examples.

What’s next

This is just the start. Additional tools will be added over the coming months, depending on the requests from developers. If there is a utility that could save you time or fill a gap, we would love to hear from you.

The goal is to build a set of genuinely useful development tools, fast to load and pleasant to use, with no sign-ups, no ads and no distractions.

You can explore the DevTools section here:
https://stablenumbers.com/devtools/