Stable Numbers: a new website I have built and published

I have been working quietly on something new and it is finally ready to share. It is called Stable Numbers.

This idea has been in my head for quite some time. I wanted to build a simple, useful, and timeless website that brings together everyday calculators, converters, finance tools, and a few developer utilities in one place. Something neat, lightweight, and genuinely helpful.

The reason I built Stable Numbers is because I love creating practical tools. Over the years I have made many small utilities for SEO, finance, and development, and I wanted a proper home for them. A single platform where people can find the kind of tools they would normally search for across several sites.

If the site gains traction and steady traffic, I will look at monetising it. For now my focus is growth through usefulness, improving the user experience, and expanding the library section by section.

A quick look around

Stable Numbers is split into a few main areas: Calculators, Conversions, Finance, Percentages, Tax, and DevTools. Each section serves a slightly different audience, from everyday users to developers and planners.

Calculators

• Age Calculator to work out exact age in years, months, and days
• BMI Calculator to check your body mass index
• Paint Calculator to estimate how much paint you will need
• Recipe Scaler to quickly adjust ingredient quantities
• Scientific Calculator for quick equations and everyday maths

Conversions

All conversion tools are fast, responsive, and straightforward.

• Centimetres to Inches
• Miles to Kilometres
• Litres to Gallons
• Square Metres to Square Feet

Finance tools

Money and planning are a big focus, so I have built a growing range of tools that help people make more informed decisions.

• Compound Interest Calculator to project savings growth over time
• Mortgage Overpayment Calculator to see potential interest savings
• ISA Growth Calculator to forecast long term savings with contributions
• Pension Pot Real Value Estimator to show how inflation affects retirement savings
• Tax Free Childcare Calculator to check family support eligibility

Tax and income

There is a mix of UK and international tax calculators, including:

• UK Take Home Pay Calculator
• Dividend Tax Calculator
• Capital Gains Tax Calculator
• US Federal Income Tax Calculator

Developer tools

A small but growing area for developers and technical users:

• Regex Tester
• JWT Debugger
• SQL Query Builder
• Grid System Calculator
• Stylesheet Generator

Why now

I have reached a point where I want to build things that hold long term value. Tools that people can bookmark, reuse, and share. Stable Numbers is built with lightweight code outside WordPress in places, which gives me full control over performance and design. Each page is SEO friendly, responsive, and designed to load quickly.

It is the kind of project that combines my technical and creative sides, and it is built to last.

Looking ahead

• More calculators and converters where they genuinely add value
• Visual dashboards for savings, mortgages, and pensions
• Selective monetisation if the audience grows, such as ads, sponsorship, or sensible affiliate partnerships

For now it is live, open to everyone, and already attracting early visitors.

Have a look

Explore everything at StableNumbers.com. If you find a tool helpful, please share it or send feedback. I would love to hear what you think.