Built to make roofing calculations easier to understand.
Roof Pitch Calculator was created to give homeowners, roofers, builders, DIY users and construction professionals a quicker, clearer way to work through everyday roofing calculations.
The idea started with a frustration I kept running into at work.
My name is Daniel Brooks, and my background is in civil engineering. After completing a Master's degree in Civil Engineering, I went on to spend around ten years working across construction and engineering projects.
Over the years, one small problem kept coming up. I would be checking measurements, reviewing drawings or trying to calculate something quickly, and finding the answer online was often harder than it needed to be.
Some calculators only worked in one unit. Others returned a number without explaining what it meant. In many cases I would move between several websites just to calculate an angle, convert a slope and understand how the numbers related to each other.
That question became the starting point for this website. You can read more about how the idea developed on Our Story.
Engineering made visual
The calculators are designed to show how measurements relate to each other instead of giving users an unexplained number.
Simple inputs. Transparent calculations. Useful outputs.
When I started building the calculators, I did not want to create another page full of boxes and technical language. The goal was to make each tool practical for someone who may not work with roofing maths every day.
That means showing users what measurements they need, where those measurements come from and what the result actually means. Wherever it helps, visual diagrams are used alongside the calculation.
The tools are based on established mathematical and geometric relationships between measurements such as rise, run, roof span, pitch angle, slope percentage, rafter length and roof area.
Where a calculation depends on a particular roof shape or assumption, the aim is to make that clear rather than silently guessing.
A calculator should do more than produce a number.
It should help the person using it understand where that number came from and what it means.
Accuracy First
Calculations are built from the underlying formulas and checked against known reference examples before being published.
Quick to Use
The aim is to get users from their measurements to a useful answer without unnecessary steps, sign-ups or downloads.
Built for Real Projects
The tools are shaped around practical roofing and construction measurements rather than abstract calculations alone.
Useful calculations should be easy to access.
I originally wanted these tools because I needed them myself. Once I started building them, it made little sense to keep them private.
Homeowners, students, tradespeople, designers, roofers and construction professionals all need these kinds of calculations. You should not need to create an account just to work out a roof angle, and you should not need specialist software just to understand a rafter length.
The idea is simple: open the calculator, enter the measurements you know and get the result.
As the site grows, the plan is to add more free roofing tools and supporting guides. You can learn more about what we are building on Our Mission.
Made for professionals and everyday users alike.
Whether you work with roofs every day or you are measuring one for the first time, the tools are designed to stay clear and approachable.
Clear calculations, with clear limitations.
A calculator is only useful if people can trust the maths behind it. That is why accuracy is treated as one of the most important parts of the project.
At the same time, every building and project is different. The results on this website are intended to support measurement, estimation and understanding. They should not replace project-specific structural calculations, building regulations, manufacturer requirements or advice from a suitably qualified professional when those are required.
The measurement entered by the user matters as well. Even a correct formula will produce the wrong result if the starting measurements are incorrect.
Start with the Roof Pitch Calculator.
Enter the measurements you know and get the roof angle, slope, pitch ratio and related measurements in seconds.