A savings number you can actually argue with

Most solar savings "calculators" are a single confident number with no workings behind it. You can't poke it, you can't check it, you just have to nod. Which is convenient — for whoever's trying to sell you something.

Ours shows you the maths.

Move the sliders, watch the range move

The Solarable savings calculator gives you an annual-benefit range and a payback range, built on stated UK assumptions: energy price, export rate, system size, and how much of your power you actually use during the day. Every one of those is on the table, and you can change it. Use a lot of electricity while the sun's up? The range moves. Out at work all day? It moves the other way. Nothing's hidden in a black box.

ScreenshotSavings calculator — annual benefit and payback ranges

ScreenshotMonthly sunlight chart for your area

Ranges, because anyone quoting you to the penny is guessing

We give you a range and we mean it. A roof's output depends on shading, pitch, kit, and a hundred small real-world things no website can see — so a tidy "you'll save £612.43 a year" is a number someone made up to look precise. We'd rather give you a band you can trust and tell you why it's a band.

The point isn't to replace a proper quote. It's to make sure that when a quote lands, you've got something honest to measure it against. If their figure sits miles outside a sensible range, you'll know to ask why — and you'll be asking from a position of actually knowing the numbers.

Run yours now — then go and make someone justify theirs.