Paint Calculator by Loom & Glow - Stop guessing how much paint your room needs

Hi Product Hunt 👋 I'm Mara from Loom & Glow. The same question kept coming up in my inbox and in every decorating forum I read: "how much paint do I actually need?" Every answer was either a vague rule of thumb or a paint brand's calculator that conveniently rounds up to the next tin. So I built the one I wanted: width, length and wall height in, litres and sensible tin sizes out. It subtracts doors and windows instead of pretending walls are solid, handles coats and the ceiling, and switches between metres and feet. The maths is open, right on the page: paintable area = 2 × (width + length) × wall height, minus ~1.8 m² per door and ~1.5 m² per window, × coats, ÷ the paint's coverage. It rounds up so you're never 20 cm short at the end of a wall. No signup, no email wall. Two things I'd genuinely like feedback on: are the coverage figures right where you live (these are UK-typical, 12 m²/L emulsion)? And what's the next decorating number you have to Google every time?