Appendix C — Measurement and Conversions

The West is split between the metric system (most of Western Europe, Canada partly, Australia, NZ) and the imperial/US customary system (the US — and the UK uses a confusing mix). Here's a quick-reference for the conversions newcomers need most.

Temperature (Fahrenheit ↔ Celsius)

The US uses Fahrenheit (°F); most others use Celsius (°C). - Formula: °C = (°F − 32) × 5/9 · · · °F = (°C × 9/5) + 32 - Quick reference:

°F °C Feels like
32 0 Freezing (water freezes)
50 10 Cold/cool
68 20 Room temperature / pleasant
77 25 Warm
86 30 Hot
95 35 Very hot
98.6 37 Body temperature
212 100 Boiling (water)
  • Rough trick: double the °C and add 30 for an approximate °F (20°C → ~70°F).

Distance and length

Imperial/US Metric
1 inch (in) 2.54 cm
1 foot (ft) = 12 in 0.30 m
1 yard (yd) = 3 ft 0.91 m
1 mile (mi) 1.61 km
— 1 km ≈ 0.62 mi
  • Quick trick: miles → km: multiply by ~1.6 (or add half: 60 mi ≈ 96 km). km → miles: multiply by ~0.6.
  • Height (US/UK use feet+inches): 5'6" ≈ 168 cm; 6'0" ≈ 183 cm.

Weight

Imperial/US Metric
1 ounce (oz) 28.3 g
1 pound (lb) = 16 oz 0.45 kg
— 1 kg ≈ 2.2 lb
1 stone (UK) = 14 lb 6.35 kg
  • Quick trick: lb → kg: divide by ~2.2 (or halve and subtract 10%). kg → lb: multiply by ~2.2.
  • Note: the UK often measures body weight in stone (e.g., "11 stone").

Volume

US Metric Note
1 fluid ounce (fl oz) 29.6 ml
1 cup ~237 ml US recipes use "cups"
1 pint (US) 473 ml UK pint = 568 ml (bigger!)
1 gallon (US) 3.79 L UK gallon = 4.55 L (bigger!)
— 1 liter (L) ≈ 0.26 US gal
  • Fuel: US sells by the gallon; most others by the liter.

Clothing & shoe sizes (approximate — always try on / check brand charts)

  • Women's clothing: US 8 ≈ UK 12 ≈ EU 40. (US and UK differ by ~4; EU is its own scale.)
  • Men's clothing: often by chest/waist in inches (US/UK) or cm (EU).
  • Shoes (women): US 8 ≈ UK 6 ≈ EU 39.
  • Shoes (men): US 10 ≈ UK 9.5 ≈ EU 44.
  • These vary by brand — use the brand's size chart and try on when possible.

Dates and time

  • Date format differs! US: MM/DD/YYYY (e.g., 03/04/2026 = March 4). UK/Europe/most others: DD/MM/YYYY (03/04/2026 = April 3). This causes real confusion — when in doubt, write the month as a word ("4 March 2026").
  • Time: US/UK commonly use 12-hour with AM/PM; much of Europe uses 24-hour ("18:00" = 6 PM).
  • Week start: US considers Sunday the first day; much of Europe, Monday.

Paper, floors, and other quirks

  • Paper size: US uses Letter (8.5 × 11 in); most others use A4 (210 × 297 mm).
  • Floors/storeys: US "first floor" = ground floor; UK/Europe "ground floor" = street level, "first floor" = one up. (So the US 2nd floor = UK 1st floor.)
  • Phone numbers, addresses, and electrical plugs/voltage also vary by country — check locally.

Keep this handy on your phone. The temperature, distance, weight, and date-format conversions are the ones you'll need almost daily.