About
Useful numbers, without the retail push.
Calculator.Shop is designed as a calm, UK-first planning library for people working through straightforward home and garden projects.
Why this exists
Material planning often starts with a few measurements, yet too many calculators hide the formula, force a product choice or bury practical limitations. This site is built around transparent tools instead.
What a good result looks like
A useful estimate states the input, shows the deduction and allowance, explains its rounding and makes it clear what still needs checking. That is the standard used here.
What happens next
Before public launch, the review record can be expanded with verified sources, version history and independently checked product-specific factors. Until then, any review source is visibly labelled as pending.