US short tons to Tonnes Converter

How it is calculated

The conversion is a single multiplication: tonnes = short tons × 0.90718474 and kilograms = short tons × 907.18474. A US short ton is 2,000 pounds, and since the pound is defined as exactly 0.45359237 kg, 2,000 pounds is 907.18474 kg, which is 0.90718474 of a metric tonne (1,000 kg). The tonne result is shown with four decimals and the kilogram result with two. The tool does not reject zero or negative numbers; a negative input simply gives a negative answer. To go the other way, divide by 0.90718474. This is the US short ton only, so the long ton of 2,240 pounds needs a different factor.

Common mistakes

• Treating the short ton and the metric tonne as the same. The short ton is about 9.3% lighter than a tonne, so on a large shipment the gap is large.
• Using this factor for the British long ton of 2,240 pounds. The long ton is heavier than a metric tonne, so the factor differs.
• Multiplying by 0.9 as a shortcut. On 25 short tons that gives 22.5 instead of 22.68, an error of about 180 kg.
• Dividing when you should multiply, which gives a number larger than the starting value. The result in tonnes must always be smaller than the short tons.
• Mixing up "ton" in a document with the tonne symbol t. Check whether a source means short tons, long tons or tonnes before converting.