Convert US Ton to Carat (ton (US) → ct)

Converting US tons to carats is straightforward: multiply by the conversion factor. Follow these three steps to do it by hand or in your head.

1. 1
   Take your value in US tons

   Start with the number of US tons (ton (US)) you want to convert.
2. 2
   Multiply by 4,535,923.7

   The conversion factor from ton (US) to ct is 4,535,923.7. Multiply your value by this number.
3. 3
   Read the result in carats

   The result is your value in carats (ct).

Multiply the value in US tons by 4,535,923.7. For the reverse direction, multiply by 2.205e-7.

• ✓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.

What is the 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).

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

What is the Carat?

The carat equals exactly 200 milligrams (0.2 g) and is the universal unit for gemstone and diamond weight in the global jewelry industry. The word derives from the Greek 'keration' and the Arabic 'qīrāṭ,' both referring to carob seeds, which were once used as natural counterweights for weighing gems because they have remarkably uniform mass. The metric carat was standardized in 1907 at exactly 200 mg, replacing dozens of regional carat values that had varied between 188 and 213 mg. A 1-carat diamond is roughly 6.5 mm in diameter, and the famous Hope Diamond weighs 45.52 carats. The carat is distinct from the karat (with a 'k'), which measures gold purity (24-karat = 100% gold). It relates to the gram (5 ct = 1 g) and the milligram (200 mg = 1 ct). Gem dealers commonly use 'points' for fractions (100 points = 1 carat).

• Diamond and gemstone retail and valuation
• Jewellery manufacturing and design
• International gem certification (GIA, IGI)