GridMonkey — Live Grid Mix
Where Britain's electricity is coming from right now — the live generation mix as one big pie, with carbon intensity, demand and interconnector flows. Group it by fuel, company, power station or wind farm. Free, no sign-up.
Open the tool → NewTreeMonkey — Carbon Translator
What does a tonne of CO₂ actually look like? Turn any amount of carbon — or your own project — into trees, car miles, flights and homes, with a scannable share card. Free forever, no sign-up.
Open the tool →U-Monkey —
U-value Calculator
Build up any wall, roof or floor and get its U-value live, to BS EN ISO 6946 and BR 443 — with a self-drawing cross-section, Part L and Future Homes Standard checks and 200+ real UK products. Completely free, including the PDF.
Open the tool →WaterMonkey — Part G Water Calculator
Part G water efficiency calcs to the official methodology — watch PASS/FAIL flip live at 125 or 110 l/p/d as you type, rainwater & greywater included. PDF reports from £25.
Open the tool →NutrientMonkey — Nutrient Neutrality Calculator
Nutrient budgets for new dwellings across all 27 Natural England catchments — nitrogen and phosphorus, NE methodology with the 20% buffer, live in your browser. Planning-ready reports £79.
Open the tool →SoakMonkey — Soakaway Calculator
Size a soakaway to BRE Digest 365 — percolation test analysis, FSR rainfall, four construction types and a climate-change uplift, all in your browser. Building Control-ready reports £25.
Open the tool →ΨMonkey — Psi Value Calculator
Work out junction Ψ-values and f_Rsi temperature factors to BS EN ISO 10211, free in your browser — no sign-up, no spreadsheet gymnastics. Stamped PDF reports for Building Control from £25.
Open the tool → NewRegs Radar
The UK building-compliance changes that actually affect your projects — Part L, the Future Homes Standard, nutrient neutrality and more — each with a straight answer on what it means. Free to read; email alerts optional.
Open Regs Radar →More Monkeys on the way
The Collection is growing — we're building more calculators for assessors and designers. Got one that would save you a headache? Tell us.
Suggest a tool →