What is a US Ton?

The US short ton equals exactly 2,000 pounds or 907.18474 kilograms, and is the standard weight unit for American freight, mining, construction, and waste management. Its name distinguishes it from the longer UK long ton (2,240 lb). The short ton emerged in the United States during the 19th century to simplify calculations: 2,000 is a rounder number than 2,240. Today it dominates American industry — coal mining quotes production in short tons, dump trucks are rated by short-ton capacity, and the EPA tracks emissions in short tons. Imperial-to-metric confusion can be costly: in 1999, the Mars Climate Orbiter spacecraft was lost partly due to a units mismatch involving pounds and newtons. The short ton relates to the pound (2,000 lb = 1 ton), the metric ton (1 short ton ≈ 0.907 t), and the long ton (1 long ton = 1.12 short tons).

Visual reference for how the us ton relates to other weight units. Each row links to the full converter for that pair.

• US freight and trucking weight limits
• US coal and mining production
• US shipbuilding and heavy industry

• ✓1 US short ton = 2000 lb = 907.18 kg.
• ✓Always clarify "short ton" in US international contracts — metric partners may assume 1000 kg.
• ✓US trucking and steel industries default to short tons; US scientific papers use metric.

• ✗Treating "ton" in US rail or truck freight as metric — the default is short ton.
• ✗Using 1000 kg as a shortcut for a US short ton — 93 kg short per ton.
• ✗Confusing short ton (907 kg) with the long ton (1016 kg) on older US paperwork.