Kilograms to Tons Converter

Kilograms to Tons

Convert kilograms (kg) to tons (t). Both measure mass and weight, and the conversion comes up in cooking, shipping, fitness work.

The Formula

`` tons = kilograms × 0.001 kilograms = tons × 1000 `

One kilogram is 0.001 tons, and one ton is 1,000 kilograms.

Conversion Table

Kilograms	Tons
1 kg	0.001 t
2 kg	0.002 t
5 kg	0.005 t
10 kg	0.01 t
25 kg	0.025 t
50 kg	0.05 t
100 kg	0.1 t
500 kg	0.5 t
1,000 kg	1 t

The Other Direction

Tons	Kilograms
1 t	1,000 kg
2 t	2,000 kg
5 t	5,000 kg
10 t	10,000 kg
25 t	25,000 kg
50 t	50,000 kg
100 t	100,000 kg
500 t	500,000 kg
1,000 t	1,000,000 kg

What Each Unit Is

Kilograms (kg) — defined since 2019 by fixing the Planck constant — the SI base unit of mass. Originally the mass of a litre of water, then a platinum-iridium cylinder near Paris until 2019.

Tons (t) — here the metric tonne: exactly 1,000 kilograms. From the tun, a large wine cask, whose weight became a trade standard.

A Sense of Scale

• A litre of water is 1 kg
• A laptop is 1.5–2 kg
• Checked baggage allowance is often 23 kg
• A small car is about 1.5 t
• A cubic metre of water is 1 t
• Shipping freight is priced per tonne

Precision

The factor 0.001 is exact by international agreement, not a rounded approximation. Any imprecision in a result comes from your input, not the conversion.

Watch Out For

• Three different tons exist: metric (1,000 kg), US short (907 kg) and UK long (1,016 kg). This converter uses the metric tonne.

In Code

`javascript const kilogramToTon = (value) => value * 0.001; ``

Where This Conversion Comes Up

• Cooking
• Shipping
• Fitness
• Medicine
• Manufacturing

How Many Decimals Do You Need?

Rounding the factor costs accuracy, and how much depends on the factor. Converting 137 kg with the factor truncated at each decimal place:

Decimals kept	Factor	137 kg becomes	Error
0	0	0	100.0000%
1	0	0	100.0000%
2	0	0	100.0000%
3	0.001	0.137	—
4	0.001	0.137	—

A rule that holds for any conversion: round once, at the end. Rounding the factor and then multiplying compounds the error through every subsequent calculation, while carrying full precision and rounding the final answer does not.

The right number of significant figures is set by your input, not by the converter. If you measured kilograms to three significant figures, the answer in tons is only good to three — writing more digits claims precision the measurement never had.