Stones to KG Converter

Last updated: June 2026

Stones

Pounds

lbs

Kilograms

63.5 kg

Formula

kg = (stones x 6.35029) + (pounds x 0.453592). One stone is exactly 14 pounds.

Quick reference table

Stones	Kilograms
8 st	50.80 kg
9 st	57.15 kg
10 st	63.50 kg
11 st	69.85 kg
12 st	76.20 kg
13 st	82.55 kg
14 st	88.90 kg
15 st	95.25 kg

About this calculator

Stones to KG Converter helps you convert stones and pounds to kilograms quickly without doing the arithmetic by hand. It is designed for everyday checks where a clear answer matters: UK body weight, medical forms, fitness tracking, international weight records. Enter a number in either side of the converter, use the swap button when you want to reverse direction, then compare the result with the quick reference table. This converter is UK-first because many people in the UK still describe body weight in stones and pounds.

Stones to KG Converter formula

The calculator applies a fixed unit conversion factor. For bidirectional conversion, the reverse formula uses the same factor in the opposite direction.

kg = (stones x 6.35029) + (pounds x 0.453592)
total pounds = kg x 2.20462, then divide by 14 for stones

How to use the stones to kg converter

Type the stones and pounds value into the first input.
Read the converted kilograms value in the second input.
Type into the second input if you want to convert in the opposite direction.
Use the swap button to change which unit appears first.
Check the formula display if you need to show your working.
Use the reference table for common values without repeated typing.

Worked examples

Example conversion

Input: 10 st 0 lbs

Calculation: 10 st 0 lbs = 10 x 6.35029 = 63.50 kg

Result: 63.50 kg

Second example

Input: 11 st 6 lbs

Calculation: 11 st 6 lbs = 69.85 + 2.72 = 72.57 kg

Result: 72.57 kg

When this conversion is useful

Use this converter when information is given in stones and pounds but your form, plan, recipe, product listing, or comparison needs kilograms. It is especially useful when mixing UK, metric, and imperial measurements.

UK body weight: Enter the source value, check the converted result, and keep enough decimal places for the level of precision needed.
Medical forms: Enter the source value, check the converted result, and keep enough decimal places for the level of precision needed.
Fitness tracking: Enter the source value, check the converted result, and keep enough decimal places for the level of precision needed.
International weight records: Enter the source value, check the converted result, and keep enough decimal places for the level of precision needed.

Rounding and precision

The live converter keeps useful decimal precision, while the reference table rounds values for readability. For casual use, rounded values are usually enough. For engineering, legal documents, medical records, building work, or purchase specifications, keep the original units and confirm the required precision before relying on a rounded number.

Common mistakes

Rounding too early and then using the rounded number in another calculation.
Mixing UK imperial and US customary units where they are not the same.
Entering a combined value in one field when the calculator expects separate units.
Copying a result without the unit label.
Using an approximate mental conversion when an exact factor is needed.

Conversion disclaimer

This converter is for general information and everyday calculation support. It does not replace professional measurement, medical, engineering, legal, or product-specific guidance where exact tolerances matter.

Reference table values may be rounded.
Source measurements can be approximate before they reach the calculator.
Some industries require specific rounding rules or certified measuring equipment.

Frequently asked questions

What is the formula for the stones to kg converter?

Use kg = (stones x 6.35029) + (pounds x 0.453592). To convert back, use total pounds = kg x 2.20462, then divide by 14 for stones.

Can I type in either input?

Yes. The converter is bidirectional, so changing either input updates the other side.

Why does my result have decimals?

Many unit conversions do not produce a whole number. Decimals keep the result more accurate than rounding to the nearest whole unit.

Should I round the answer?

For everyday use, rounding to one or two decimals is often fine. For technical work, keep more decimal places and follow the rounding rule required for that task.

Are UK and US units always the same?

No. Some units, especially gallons and fluid ounces, differ between UK imperial and US customary systems. Use the converter that matches the system you need.

Related calculators

KG to Stones Converter
Stones to Pounds Converter
BMI Calculator
Healthy Weight Calculator

What does this mean?

This calculator is designed to help you understand the likely number before you make a decision or start an application.

Your result should be checked against official UK guidance, especially if your circumstances include dependants, exemptions, prior leave, or a complex immigration history.

Treat the figure as a planning tool rather than legal advice. Where the answer affects an application deadline or major payment, speak to an authorised adviser.