Tonne (t)

Definition

Exactly 1000 kilograms — the metric ton.

History

The tonne, or metric ton, was defined as exactly 1000 kilograms as the metric system spread, giving a convenient unit for heavy loads. It is accepted for use with the SI.

Where it is used

Tonnes measure bulk and freight weight, vehicle mass and industrial quantities throughout the metric world.

Typical uses include bulk and freight weight, vehicles.

Conversion pages

These pages convert tonne to or from another unit in weight.

• Kilogram to tonne

Other Weight units

• Kilogram (kg)
• Gram (g)
• Pound (lb)
• Ounce (oz)
• Stone (st)
• Milligram (mg)
• Microgram (mcg)

Sources

• BIPM SI BIPM, The International System of Units (SI), 9th ed. (2019) · Dataset reviewed Nov 11, 2026