Imperial conversions

Both directions. Dozenal-side values are dozenal; imperial-side values are decimal (as imperial is used now). UK and US units differ for volume and tons.

Quantity Imperial = dozenal units Dozenal unit = imperial (dec)
Length 1 inch 2;627 di 1 di = 0.3971 in
Length 1 foot 2;627 un 1 un = 0.3971 ft (4.765 in)
Length 1 yard 0;767X p 1 p = 1.589 yd (4.765 ft)
Length 1 mile 783;E p (0;784 ir) 1 ir = 1.560 mi
Length 1 nautical mile 8X3 p (0;E5X na) 1 na = 1.045 nmi
Length 1 furlong E6;6 p 1 ir = 12.48 furlongs
Area 1 square foot 6;41 un² 1 un² = 0.1577 sq ft
Area 1 acre 1;13X ag 1 ag = 0.9009 acre
Mass 1 ounce 2;37X b↓li 1 b↓li = 0.4339 oz
Mass 1 pound 0;30X6 li 1 li = 3.905 lb
Mass 1 stone 3;703 li 1 li = 0.2790 st
Mass 1 ton (UK long) 3E9;7 li
Mass 1 ton (US short) 368;1 li
Volume 1 fl oz (UK) 23;82 t↓cu 1 t↓cu = 0.03612 fl oz (UK)
Volume 1 fl oz (US) 24;99 t↓cu 1 t↓cu = 0.03471 fl oz (US)
Volume 1 pint (UK) 0;3X18 cu 1 cu = 3.121 pt (UK)
Volume 1 pint (US) 0;325 cu 1 cu = 3.748 pt (US)
Volume 1 gallon (UK) 2;691 cu 1 cu = 0.3901 gal (UK)
Volume 1 gallon (US) 2;174 cu 1 cu = 0.4685 gal (US)
Volume 1 cup (US) 0;1726 cu 1 cu = 7.496 cups (US)
Speed 1 mph 1;348 p/br 1 p/br = 0.7798 mph
Speed 1 knot 1;586 p/br 1 p/br = 0.6776 knot
Energy 1 Calorie (kcal) E2;E op 1 t↑op = 12.80 kcal
Energy 1 BTU 2X;05 op 1 op = 0.02938 BTU
Power 1 horsepower 8;429 vg 1 vg = 0.1197 hp
Pressure 1 psi 0;4897 t↑pr 1 t↑pr = 2.535 psi
  • A mile ≈ 0;8 iter (two-thirds of an iter, 1.67 km; the mile is 4% shorter). Half an iter (1.25 km) sits between a kilometre and a mile
  • Inch → dig and foot → unc give the same digits (2;627), because both systems step by twelve there
  • The name links too: Latin uncia (a twelfth) is the root of both inch (1/12 foot) and ounce (1/12 Roman pound)

Fahrenheit

°t = (°F - 32) × 0.8001 (decimal arithmetic, then convert) - so roughly (°F - 32) × 4/5.

°F °t Note
0 -21;7
32 0 freezing
50 12;5
68 24;X room
98.6 45;3 body
100 46;5
212 100 boiling
350 192 oven