A kilogram(kg) is the base unit of mass in the International System of Units (SI) and it was originally defined as the mass of one liter of water.

While a tonne(t) is a metric unit of mass equal to 1,000 kilograms.

**Formula to convert kilograms to tonnes.**

Since we already know the relation between a tonne and a kilogram from the definition which is;

1000kg = 1 t

Therefore, when converting kg to t, we divide the kg by 1000.

**Mass in t = Mass in kg ÷ 1000**

**Example:**

Convert 3500 kg to tonnes.

**= 3500** ** ÷ 1000**

**= 3.5 tonnes.**