Measuring weight can be tricky. The world uses different systems, like the metric system (kilograms) and the imperial system (pounds, ounces, and stones). Sometimes, you need to switch between them, and that’s where things get confusing.
This article breaks down the relationship between kilograms and stones. We’ll define both units and explain exactly how to convert from one to the other. Knowing exactly how many kilos in a stone can be helpful if you live somewhere that still uses stones or need to understand measurements in older texts.
What is a stone?
A “stone” is a unit of weight. Specifically, one stone equals 14 pounds (lb) or 6.3503 kilograms (kg).
You’ll hear this measurement used frequently in the UK, Australia, and Ireland, especially when talking about a person’s body weight. Someone might say, “I weigh 12 stone,” instead of saying their weight in pounds or kilograms.
Historically, the term “stone” comes from the practice of using actual stones as weights for measuring goods. Over time, it became a standardized unit, though its use is now largely limited to the contexts mentioned above.
What is a Kilogram?
Okay, so we’ve established that a stone equals a little over 6 kilograms. But what is a kilogram, anyway?
A kilogram is a unit of mass in the metric system. Think of it this way: 1 kilogram is the same as 1,000 grams. It’s also the base unit of mass in the International System of Units (SI), which is the standard for scientists.
Interestingly, the definition of a kilogram has changed over time. It used to be based on a physical object, a platinum-iridium cylinder locked away in France. Now, it’s defined using something called the Planck constant, which is a fundamental constant of nature. This makes the definition much more precise and stable.
Kilograms are used all over the world, especially in countries that use the metric system. It’s a fundamental unit for measuring weight and mass in everyday life and in scientific applications.
How many kilograms in a stone?
Okay, so here’s the deal. The relationship between kilograms and stones is fixed, but you’ll often see rounded numbers in everyday use. The precise conversion is:
- 1 stone = 6.35029318 kilograms
- 1 kilogram = 0.157473 stones
Basically, if you need to convert stones to kilograms or vice-versa, just remember those numbers. But don’t be surprised if you see slightly different figures floating around – rounding is super common!
Converting kilograms to stones
So, you want to convert your weight from kilograms to stones? Here’s what you need to know.
The conversion formula
To convert kilograms to stones, you’ll use this formula:
stones = kilograms × 0.157473
All you have to do is multiply your weight in kilograms by the conversion factor of 0.157473, and that’ll give you your weight in stones.
Example conversion
Let’s say you weigh 70 kg. To convert that to stones, you’d do this:
stones = (70 kg × 0.157473) = 11.02311 st
For practical purposes, you’d probably round that to 11.02 stones.
Converting kilograms to stones and pounds
If you want to get even more precise and figure out your weight in both stones and pounds, here’s how to do it:
- Divide your weight in kilograms by 6.35029318 to get the stone value.
- The whole number is your weight in stones, and you’ll use the decimal for the next step.
- Multiply the decimal by 14 to get pounds.
For example, if you weigh 70 kg, you’d divide 70 by 6.35029318, which equals about 11.02. So, you weigh 11 stones and a fraction of a stone. To figure out the pounds, multiply that decimal of 0.02 by 14, and you get approximately 0.28 pounds. So, 70 kg is approximately 11 stones and a quarter of a pound.
Converting stones to kilograms
So, how do you turn stones into kilograms? It’s actually pretty simple.
The conversion formula
The formula you’ll use is this:
kilograms = stones × 6.350293
Just multiply the number of stones by that factor (6.350293), and you’ll have your answer in kilograms.
Example conversion
Let’s say you want to convert 12 stones into kilograms. Here’s how you’d do it:
kilograms = (12 st × 6.350293) = 76.203516 kg
In practical terms, you’d probably round that to 76.2 kg.
Converting stones and pounds to kilograms
Sometimes, you might have a measurement in both stones and pounds. No problem! Here’s what you do:
- Multiply the number of stones by 6.35029318.
- Multiply the number of pounds by 0.45359237.
- Add those two results together.
That sum will give you the weight in kilograms.
Practical Applications and Conversion Tools
Knowing how to convert between stones and kilograms can be useful in many situations. For example, when you’re tracking your weight for health and fitness purposes, or when you’re traveling or communicating with people from other countries.
Luckily, you don’t have to do the math yourself! Online calculators and conversion charts make it super easy and accurate to convert between these units. Just type in the number of stones, and the calculator will instantly show you the equivalent weight in kilograms (and vice versa!).
Even better, many modern scales can display your weight in multiple units. You can often choose whether you want to see your weight in pounds, kilograms, or even stones, making it incredibly convenient to track your progress in whatever unit you prefer.
Closing Thoughts
So, a stone is equal to 14 pounds, and a kilogram is about 2.2 pounds. That means there are roughly 6.35 kilograms in a stone.
Even though the metric system is pretty standard in science and most countries, knowing what a “stone” means is still helpful, especially if you’re in the UK or talking with someone who uses that measurement.
And hey, if you ever get confused, there are tons of easy-to-use converters online. No need to do the math in your head!