Unit converter

Kilograms to stone and pounds.

Convert kg to st + lb and st + lb to kg. Type in either box and the other follows. UK body weight is said as stone and pounds, so 80 kg is 12 st 8.4 lb rather than 12.6 stone.

kg → st + lbExact definition
Kilograms to stone and pounds — common values, to 6 significant figures.
kgst + lb
50 kg7 st 12.23 lb
55 kg8 st 9.25 lb
60 kg9 st 6.28 lb
65 kg10 st 3.3 lb
70 kg11 st 0.32 lb
75 kg11 st 11.35 lb
80 kg12 st 8.37 lb
85 kg13 st 5.39 lb
90 kg14 st 2.42 lb
95 kg14 st 13.44 lb
100 kg15 st 10.46 lb
110 kg17 st 4.51 lb
1 st=14 lb 1 st=6.35029318 kg

Definitions

  • The kilogram is the SI base unit of mass, defined since 2019 by fixing the Planck constant rather than by a metal cylinder in Paris.
  • Stone and pounds together, the way UK body weight is quoted. Fourteen pounds to the stone.
  • This conversion is exact by definition. 80 kg = 12 st 8.37 lb.
  • Everything here is mass, not force. The pound is defined as exactly 0.453 592 37 kg, so pound-to-kilogram conversion is exact.

How it works

One direction multiplies and the other divides by the same number, so nothing is lost by going back and forth.

The value passes through kg, the unit every other mass & weight unit on the site is defined against, rather than a number written into this page on its own. That is why the figure here, the figure in the table above and the general mass & weight converter always agree.

Display precision limits significant figures rather than decimal places, because one fixed number of decimals is useless across a range this wide. Very large and very small results switch to scientific notation with a proper superscript exponent. The editable box always holds a plain number at full working precision, so you can carry on from either side.

Common questions this answers: what 80 kg is in stone and pounds (12 st 8.37 lb), how many pounds make a stone (14), and how to type it — "5 st 9 lb" or just "5 9" are all accepted.