Convert Mass from Kilogram to Ton (kg to t)
Multiple conversions

Kilogram to Ton Conversion Formula

To convert from Kilogram (kg) to Ton (t), use the following formula:

With $\frac{1}{453.59237}$ is the ratio between the base units Pound (lb) and Gram (g).

Example

Let's convert 5 Kilogram (kg) to Ton (t).

Using the formula:

Therefore, 5 Kilogram (kg) is equal to $0.005511556554621939518$ Ton (t).

What is a Kilogram (kg)?

A kilogram (kg) is the base unit of mass in the metric system, used worldwide to measure everything from your body weight to the groceries you buy.

It's equal to 1,000 grams (g).

For a simple real-world comparison, the mass of a one-liter bottle of water is almost exactly one kilogram.

Key Takeaways

• A kilogram is 1,000 grams.
• The kilogram is now defined by the Planck constant, a fundamental constant of nature.
• Previously, it was defined by a physical metal cylinder in France named "Le Grand K."
• It is the only SI base unit that has a prefix ("kilo") in its name.

How Is the Kilogram Defined Today? From an Object to a Constant

For more than 130 years, the kilogram was a physical object: a platinum-iridium cylinder called the International Prototype Kilogram (IPK), also known as "Le Grand K," which was kept under tight security near Paris.

Scientists eventually found the problem — the artifact was losing an imperceptible amount of mass over time — so it couldn't guarantee the long-term accuracy required by science and industry.

On May 20, 2019, the kilogram was redefined.

It's no longer tied to a single object but to a fundamental constant of nature: the Planck constant (h). That change makes the kilogram stable and reproducible with precision anywhere in the universe.

What Was the Original Definition of the Kilogram?

The kilogram's story begins during the French Revolution with the creation of the metric system. The original definition, established in 1795, was beautifully simple and practical.

The gram was first defined as the mass of one cubic centimeter of water at 4 °C (39.2 °F), the temperature at which it is most dense.

From there, the kilogram was defined as the mass of one liter (one cubic decimeter) of water under the same conditions. This practical, water-based definition was a revolutionary step toward a global standard of measurement.

Why Is the Kilogram a Unique SI Base Unit?

The International System of Units (SI) is built on seven base units that serve as the foundation for all measurements. These include the meter for length, the second for time, and the ampere for electric current.

The kilogram is a historical oddity, as it's the only SI base unit with a prefix ("kilo").

Due to its origins, the kilogram, rather than the gram, became the fundamental unit of mass, making it a curious exception in the measurement system.

What is a Ton (t)?

A ton (t) is a standard unit of mass.

In the United States, a ton is equivalent to 2,000 pounds (lb).

That said, the exact amount can vary depending on the system you use—US, British (Imperial), or metric—so it's essential to know which "ton" you mean to avoid mistakes.

How Many Pounds Are in a Ton? Short vs. Long vs. Metric

While the US short ton is widely used, it's not the only definition.

The three main types of tons have different weights:

• Short Ton (US): This is the standard ton in the United States. It equals 2,000 pounds.
• Long Ton (UK): Also known as the imperial ton, this is used in the United Kingdom. It equals 2,240 pounds.
• Metric Ton (Tonne): Used globally in the metric system, a tonne is defined as 1,000 kilograms. This is equal to approximately 2,204.6 pounds.

The distinction between these units is crucial in international shipping and trade to avoid costly confusion.

Ton vs. Tonne: Why Spelling Matters

The spelling of the word tells you exactly which measurement system is being used.

• "Ton" refers to the imperial units—either the short ton (2,000 lbs) or the long ton (2,240 lbs).
• "Tonne" (spelled with an "ne") specifically refers to the metric unit of 1,000 kilograms.

Using "tonne" ensures precision and is the standard unit of measurement for science and international commerce.

The Surprising Origin of the Ton Measurement

The word "ton" originates from the Old English "tunne," which was a large cask used for storing wine, also known as a tun.

These casks were so typical that the weight of a full one became a standard unit of measurement.

Over time, this was standardized to 2,000 pounds, becoming the ton we use in the United States today.

What is the metric system?

What is the imperial system?

Kilogram to Ton Conversion Table

Here are some quick reference conversions from Kilogram (kg) to Ton (t):