Hands-on & hardware

DIY

Reference tools for hands-on work around the house and workshop — starting with how paint colours actually combine when you mix them for real, not how light does on a screen.

Paint Colour Mixing

Mix real pigment colours the way a subtractive palette actually behaves — blue and yellow make green, not grey.

RYB subtractive mixing, not RGB
Open

Room Colour Visualiser

Paint a 3D room with your own mixed colours and watch the light bounce. Matt through gloss, six room shapes, and a choice of floor.

Paint Coverage Calculator

Room dimensions to litres and cost, with real coverage rates by paint type and surface porosity.

L = area × coats ÷ coverage
Open

Screw, Stud & Tap Drill Sizing

The right fixing for the wall and the weight, plus UK stud spacing standards and a screw gauge reference.

stud centres: 400mm or 600mm
Open

Tea & Coffee Brewing Calculator

Pick the shade you want and get the exact brew time — real extraction kinetics, teabag vs. loose leaf, any mug size.

strength = max·(1 − e^(−kt))
Open

Egg Timer Calculator

Real heat-transfer physics for boiling, poaching, frying and scrambling any egg — all sizes, bird types and doneness levels, with a working countdown timer.

t = M^⅔·c·ln[0.76·(T_egg−T_water)/(T_yolk−T_water)]
Open

Steak Timer & Doneness Calculator

Cooking times solved from real heat conduction — set by thickness, not weight — with a live timer that says when to flip, when to pull and how long to rest.

∂T/∂t = α·∂²T/∂x² — t ∝ thickness²
Open

Concrete Mix Calculator

Cement, sand, aggregate and water for any volume and grade — real mix ratios and the dry-volume correction.

1:2:4 by weight · 1.54× dry factor
Open

Precision Timer & Stopwatch

Drift-corrected stopwatch with real lap statistics, a multi-timer, interval trainer, precision metronome, and reaction-time tester.

elapsed = now − startTime, always
Open
Results are for reference only. Real paint, materials and finishes vary by brand and batch — check against a physical sample before committing.