Stones & Pounds to Kilograms Converter (st to kg)

Convert stones and pounds to kilograms (st & lbs to kg). Enter stones and additional pounds for instant results in kg, grams, and total pounds.

st
lbs (0–13)

WEIGHT IN KILOGRAMS

63.5 kg


GRAMS

63503 g

TOTAL POUNDS

140 lbs

STONE + LBS

10 st 0 lbs

FORMULA

140 Γ— 0.4536

Stones to Kilograms β€” Reference Table

StonesPoundsKilogramsGrams
1 st14 lbs6.35 kg6350 g
2 st28 lbs12.70 kg12701 g
3 st42 lbs19.05 kg19051 g
4 st56 lbs25.40 kg25401 g
5 st70 lbs31.75 kg31751 g
6 st84 lbs38.10 kg38102 g
7 st98 lbs44.45 kg44452 g
8 st112 lbs50.80 kg50802 g
9 st126 lbs57.15 kg57153 g
10 st140 lbs63.50 kg63503 g
12 st168 lbs76.20 kg76204 g
15 st210 lbs95.25 kg95254 g
20 st280 lbs127.01 kg127006 g
30 st420 lbs190.51 kg190509 g

How to Convert Stones to Kilograms

One stone equals exactly 14 pounds, or 6.350293 kilograms. To convert stones (with optional additional pounds) to kilograms:

Step 1: Convert to total pounds: total lbs = (stone Γ— 14) + additional pounds
Step 2: Convert pounds to kilograms: kg = total lbs Γ— 0.453592

Or directly: kg = stone Γ— 6.350293

Example: 11 stone 4 lbs = (11 Γ— 14) + 4 = 158 lbs = 158 Γ— 0.453592 = 71.67 kg

Stones to Kilograms Conversion Chart

Quick reference for common stone-to-kg conversions:

StonesPoundsKilogramsApproximate BMI Context
7 st98 lbs44.45 kgLightweight adult
8 st112 lbs50.80 kgSmall adult
9 st126 lbs57.15 kgAverage woman (UK)
10 st140 lbs63.50 kgβ€”
11 st154 lbs69.85 kgAverage man (UK)
12 st168 lbs76.20 kgβ€”
13 st182 lbs82.55 kgAverage man (US)
14 st196 lbs88.90 kgβ€”
15 st210 lbs95.25 kgβ€”
16 st224 lbs101.61 kgβ€”
18 st252 lbs114.31 kgβ€”
20 st280 lbs127.01 kgβ€”
25 st350 lbs158.76 kgβ€”
30 st420 lbs190.51 kgβ€”

Stone + Pounds β€” Common Body Weights

Since body weight is rarely a round number of stones, here are common weights with pounds included:

Stone & PoundsTotal PoundsKilograms
8 st 7 lbs119 lbs53.98 kg
9 st 4 lbs130 lbs58.97 kg
10 st 0 lbs140 lbs63.50 kg
10 st 7 lbs147 lbs66.68 kg
11 st 0 lbs154 lbs69.85 kg
11 st 7 lbs161 lbs73.03 kg
12 st 0 lbs168 lbs76.20 kg
12 st 7 lbs175 lbs79.38 kg
13 st 0 lbs182 lbs82.55 kg
14 st 0 lbs196 lbs88.90 kg
15 st 7 lbs217 lbs98.43 kg

What Is a Stone?

The stone (abbreviation: st) is an imperial unit of weight equal to 14 pounds (6.35 kg). It's primarily used in the United Kingdom and Ireland to measure body weight. When a British person says "I weigh 11 stone," they mean 154 pounds (69.85 kg).

The stone has ancient origins β€” it was historically the weight of a literal stone used as a counterweight on balance scales. Different trades used different "stone" weights until 1824, when the UK Weights and Measures Act standardized it at 14 pounds.

Today, the stone is not recognized in the US, where pounds are used exclusively for body weight. It's also not an official SI unit, but remains deeply embedded in British and Irish culture.

What Is a Kilogram?

The kilogram (abbreviation: kg) is the SI base unit of mass, equal to 1,000 grams or approximately 2.205 pounds. Since 2019, the kilogram has been defined by the Planck constant (replacing the physical platinum-iridium prototype stored in France since 1889).

Kilograms are used worldwide for body weight β€” except in the US (which uses pounds) and UK/Ireland (which use stones and pounds). Most medical records globally use kilograms.

US vs. UK vs. Metric Weight Systems

  • United States: Body weight measured in pounds (lbs). "I weigh 175 pounds."
  • United Kingdom & Ireland: Body weight measured in stones & pounds. "I weigh 12 stone 7." (= 175 lbs = 79.4 kg)
  • Most other countries: Body weight measured in kilograms. "I weigh 79 kg."

This creates frequent conversion needs when Americans encounter British weight references (TV shows, sports, news), or when filling out international medical forms.

When to Convert Stones to Kilograms

  • Understanding British body weight references: UK TV shows, news, and fitness content use stones. "She lost 2 stone" = she lost 28 lbs (12.7 kg).
  • Medical and fitness tracking: International health apps and medical records use kilograms. If you know your weight in stones, you need to convert for BMI calculations, medication dosing, or gym programs.
  • International travel: Airline baggage limits, visa medical exams, and hotel scales in Europe all use kilograms.
  • Combat sports: Boxing and MMA weight classes are listed in pounds in the US but sometimes in stones in the UK (e.g., "welterweight" = 10 st 7 lbs = 147 lbs = 66.7 kg).
  • Immigration and visas: Medical examination forms for UK and US visas require weight in specific units β€” converting between systems is often necessary.

Stones & Pounds to Kilograms Converter (st to kg) FAQ