Measurement guides
Twelve reference guides that go past the number: what each measurement actually describes, where it is used, and the mistakes that cost people money.
TV & monitor screen sizes
What a screen size in inches actually measures, how wide each popular size really is, and how to check a TV fits before it arrives.
Height: feet, inches and cm
How to convert height between feet, inches and centimetres without the classic 5.10 mistake, plus a chart of common adult heights.
Weight: kg, pounds and stone
Convert body weight between kilograms, pounds and stone accurately — including why the 2.2 shortcut fails at higher weights.
Airline luggage limits
Cabin and checked baggage limits in both centimetres and inches, how airlines measure them, and where travellers get caught out.
Running distances
Every standard race distance in both miles and kilometres, with pace conversions and the splits runners actually use.
Baking measurements
Why cups fail in baking, how to convert American recipes to grams, and the tin sizes that change your bake most.
Tyre and wheel sizes
How to read a tyre code that mixes millimetres, percentages and inches — and what each number means for fit.
Pipe and thread sizes
Why a half-inch pipe measures neither 12.7 mm nor anything close, and how nominal sizes relate to real dimensions.
Paper sizes: A4 and Letter
A4 versus US Letter in millimetres and inches, why the A series halves so neatly, and how to print across both.
TV viewing distance
The viewing distance that suits each screen size and resolution, worked out in both metres and feet.
Shipping weights
How couriers charge for parcel size rather than mass, the divisors they use, and how to convert between systems.
Monitor size and PPI
How screen size and resolution combine into pixel density, and which combinations look sharp at desk distance.
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How these guides are written
Each one starts from a real question, uses primary sources for its figures, and is checked by a second person before it goes live.
Question first
Each guide starts from a real search — the thing people actually need to settle.
Official figures
Definitions come from standards bodies, not from other websites.
Worked examples
Numbers are shown in context so you can check the maths yourself.
Reviewed twice
Every figure is verified by a second person before publication.
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