Stone to KG Converter

Convert stone to kilograms (st to kg)

To convert stone to kilograms, multiply the value in stone by 6.35029318. Most visitors are converting a UK or Irish body weight given in stone into kilograms for a gym, doctor or fitness app. This stone to kg converter works both ways: type stone or kilograms into either box above and the other box, the worked formula and the chart below update as you type.

The stone (st) is a British unit of weight equal to 14 pounds, or exactly 6.35029318 kilograms. It is still the usual way to talk about body weight in the UK and Ireland — someone might weigh 11 st 4 lb — but it is rarely used anywhere else. One stone is 6.35029 kilograms.

The kilogram (kg) is the SI base unit of mass. Since 2019 it has been defined through the Planck constant instead of a platinum-iridium cylinder kept near Paris. Going the other way, one kilogram equals 0.157473 stone. Kilograms are used for body weight, groceries, luggage allowances and shipping in almost every country.

How to convert stone to kg with this tool

1. Type a number into the Stone (st) box — it starts at 10 st as an example.
2. Read the answer in the Kilograms (kg) box and in the result panel, which also shows the formula with your number.
3. To go the other way, type into the kilograms box, or press the swap button to open the KG to Stone converter with your value carried over.
4. Choose how many decimal places you want, or tap a quick value such as 8 st, 10 st, 12 st.
5. Press Copy result to paste the conversion into a message, spreadsheet or note.

Stone to KG converter features

Stone to KG formula

The formula is kg = st × 6.35029318. It is exact because a stone is 14 pounds of 0.45359237 kg, which makes it exactly 6.35029318 kilograms.

The reverse formula is st = kg ÷ 6.35029318 — or use the KG to Stone converter. Three worked examples:

• A weight of 10 stone: 10 st × 6.35029318 = 63.5029 kg
• 12 st 7 lb (12.5 st): 12.5 st × 6.35029318 = 79.3787 kg
• A weight of 16 stone: 16 st × 6.35029318 = 101.6047 kg

Stones and pounds

UK weights are usually written as stones plus pounds: 11 st 6 lb means 11 stone and 6 pounds, or 160 lb in total. To enter that here, use decimal stones — 11 + 6 ÷ 14 = 11.4286 st.

For that example, 11.4286 st = 72.575 kg. The line under the result turns any decimal stone value back into stones and pounds, so you can check what you typed.

Stone to KG quick reference

The values people look up most often, worked out with the exact factor:

• 1 st = 6.35029 kg
• 1 kg = 0.157473 st
• 8 st = 50.8023 kg
• 10 st = 63.5029 kg
• 12 st = 76.2035 kg
• 14 st = 88.9041 kg

Quick tip: Multiply by 6.35, or for a rough figure by 6⅓: 12 st ≈ 76 kg, versus the exact 76.2035 kg.

Related conversions: LBS to KG, KG to LBS and the full weight converter.

Stone to KG conversion table

Values in kilograms are rounded to 4 decimal places (more for very small numbers). For any value not listed, type it into the converter above.