Convert Weight from Metric Tonnes to Stones (mt to st)

Metric Tonne to Stone Conversion Formula

Example

Let's convert 5 Metric Tonne (mt) to Stone (st).

Using the formula:

Therefore, 5 Metric Tonne (mt) is equal to 787.3652220888485026 Stone (st).

How many metric tonnes are in one stone? One Stone (st) contains 0.00635029318 Metric Tonnes (mt) — the inverse of the factor above. Multiplying by 157.47304441776970052 takes you from metric tonnes to stones; multiplying by 0.00635029318 brings you back.

Put in words: one metric tonne equals 157.47304441776970052 stones, so the metric tonne is the larger unit of this pair. Converting between them never changes the amount of weight being measured — only the size of the unit you count it in.

What is a Metric Tonne (mt)?

A metric tonne, often called simply a tonne (symbol: t), is a standard unit of mass in the metric system.

It's commonly used around the world to measure heavy objects, especially in trade and industry.

So, how heavy is it?

• A metric tonne is exactly 1,000 kilograms.
• This is equal to about 2,204.6 pounds.

It's also equivalent to one million grams (10⁶ g), which is why it's sometimes called a megagram (Mg).

The Simple Link Between a Tonne and Water

A great way to visualize a metric tonne is to think of a cube of water.

Imagine a cube that's one meter on each side—one meter tall, one meter wide, and one meter long. If you were to fill that cube with pure water, its mass would be exactly one metric tonne (1,000 kilograms).

This simple and direct relationship between volume (1 m³) and mass (1 tonne) is a perfect example of what makes the metric system so logical and practical.

Tonne vs. Ton: What's the Difference?

The term "ton" can be confusing, as it refers to different units of weight depending on the location.

Understanding this distinction is crucial, especially in the context of international shipping.

• Metric Tonne (t): The standard international unit. It's 1,000 kg or 2,204.6 lbs.
• Short Ton (US Ton): Commonly used in the United States, equal to exactly 2,000 pounds (about 907.2 kilograms).
• Long Ton (UK Ton): A traditional British unit of weight, equal to 2,240 lbs (about 1,016 kg).

Key takeaway: A US short ton is roughly 10% lighter than a metric tonne, whereas a UK long ton is slightly heavier. Always specify the unit to prevent costly errors!

What is a Stone (st)?

The stone (st) is a unit of measurement equal to 14 pounds (lb).

It's part of the imperial system and is still commonly used in a few countries, especially for weighing people.

How Many Kilograms are in a Stone?

For use in international contexts or scientific applications, the stone is often converted to the metric system.

One stone is equal to exactly 6.35029318 kilograms (kg).

This precise conversion is used in international trade and science to ensure everyone is using the exact standard measurement.

Why is Body Weight Measured in Stone?

Although it's an older unit, the stone remains the primary unit of measurement for body weight in the United Kingdom and Ireland.

It's common to hear someone state their weight as a combination of stone and pounds, like "12 stone 6 pounds."

Where Did the Stone Unit Come From?

The stone traces its origins back to the medieval English wool trade, where a "stone of wool" referred to a standard 14-pound measure used for buying and selling.

Stones for other goods could vary in weight—for example, a stone of glass was just 5 pounds—but over time, the 14-pound stone became the official legal standard.

How the Stone Is Actually Written

The stone is almost never used on its own. Body weight in Britain and Ireland is quoted as stones and pounds, with the remainder written out rather than expressed as a decimal.

A person weighing 72 kg is "11 stone 4" — that is 11 st 4 lb, or 158 pounds — not "11.3 stone". Reading the decimal form as pounds is a common error: 11.3 st is 11 st 4.2 lb, close by coincidence, but 11.5 st means 11 st 7 lb, not 11 st 5 lb.

The conversions worth keeping to hand are:

• 1 stone = 14 pounds = 6.35029 kilograms
• 1 kilogram ≈ 0.157473 stone
• A useful mental check: 10 stone ≈ 63.5 kg, and each additional stone adds a little over 6 kg.

Where the Stone Is and Is Not Used

The unit's survival is unusually specific. It was removed from British trade use by weights and measures legislation, so nothing is sold by the stone — shop scales read in kilograms and grams.

What survives is personal and conversational use: body weight, and by extension the weight of livestock and sporting figures such as boxing and horse-racing weights. Medical records in the UK are kept in kilograms, but patients are routinely told their weight in stones and pounds because that is the number they recognise.

Outside Britain and Ireland the unit is essentially unknown. The United States, despite sharing the pound, does not use the stone at all — American body weight is quoted in pounds alone, which is why a US figure of "158 lb" and a UK figure of "11 st 4" describe exactly the same person.

Metric Tonne to Stone Conversion Table

Here are some quick reference conversions from Metric Tonne (mt) to Stone (st):