Convert Carats to Long tons
1 carat is 1.97e-7 LT. One carat is exactly 1.96841305522e-7 long tons.
One carat is 1.9684 × 10^-7 long tons. To convert carats to long tons, multiply by 1.9684 × 10^-7; to go the other way, divide by 1.9684 × 10^-7 or multiply by 5.0802 × 10^+6. The relation is exact but the figure is not: it is a rounding of a number that does not terminate, and it follows from NIST Handbook 44. Exactly 200 milligrams, fixed by international agreement in 1907 after centuries of local carats.
Factor checked against the defining standard · How we check
- Carats × 1.9684 × 10^-7
1 * 0.00000020 LT
1 carat in every weight unit
| Unit | Value | Exact factor |
|---|---|---|
| ounces | 0.00705479239 oz | × 0.00705479238992 |
| pounds | 0.0004409245244 lb | × 0.00044092452437 |
| stone | 0.00003149460888 st | × 0.0000314946088836 |
| US tons | 0.0000002204622622 ton | × 0.000000220462262185 |
| micrograms | 200,000 mcg | × 200,000 |
| milligrams | 200 mg | × 200 |
| centigrams | 20 cg | × 20 |
| grams | 0.2 g | × 0.2 |
| kilograms | 0.0002 kg | × 0.0002 |
| slugs | 0.00001370435317 slug | × 0.0000137043531714 |
| tonnes | 0.0000002 t | × 0.0000002 |
| carats (as entered) | 1 ct | — |
| troy ounces | 0.006430149314 ozt | × 0.00643014931373 |
| grains | 3.086471671 gr | × 3.08647167059 |
| long tons | 0.0000001968413055 LT | × 0.000000196841305522 |
Factors are entered by hand from NIST Handbook 44 rather than derived from a units library, so the ones that terminate are exact rather than rounded.
How do you convert carats to long tons? The converter and the working
- 1.Take the measurement in carats.
- 2.Multiply by 1.9684 × 10^-7 — that is how many long tons fit in one carat.
- 3.To go back the other way, divide by 1.9684 × 10^-7, or multiply by 5.0802 × 10^+6.
Worked example: 25 carats to long tons
- Formula
- ct × 1.9684 × 10^-7 = LT
- Arithmetic
- 25 × 1.9684 × 10^-7 = 0.000004921 LT
- Answer
- 25 ct = 0.000004921 LT
The factor is rounded for display; the figure above is computed from the full value.
Carats to long tons conversion table
| Carats | Long tons |
|---|---|
| 1 ct | 1.97e-7 LT |
| 2 ct | 3.94e-7 LT |
| 3 ct | 5.91e-7 LT |
| 4 ct | 7.87e-7 LT |
| 5 ct | 9.84e-7 LT |
| 6 ct | 0.000001181 LT |
| 7 ct | 0.000001378 LT |
| 8 ct | 0.000001575 LT |
| 9 ct | 0.000001772 LT |
| 10 ct | 0.000001968 LT |
| 12 ct | 0.000002362 LT |
| 15 ct | 0.000002953 LT |
| 20 ct | 0.000003937 LT |
| 25 ct | 0.000004921 LT |
| 50 ct | 0.000009842 LT |
| 100 ct | 0.00001968 LT |
| 200 ct | 0.00003937 LT |
| 300 ct | 0.00005905 LT |
| 500 ct | 0.00009842 LT |
| 1000 ct | 0.0001968 LT |
| 2000 ct | 0.0003937 LT |
| 5000 ct | 0.0009842 LT |
| 10000 ct | 0.001968 LT |
What is a carat?
Exactly 200 milligrams, fixed by international agreement in 1907 after centuries of local carats. It weighs a gemstone; the karat that grades gold is a different word for a different thing — purity in twenty-fourths.
What is a long ton?
The British ton: 2,240 lb, against the US short ton’s 2,000 and the tonne’s 2,204.62. Three units, one word, and shipping documents use all three.
How many long tons are in a carat?
One carat is 1.9684 × 10^-7 long tons. Going the other way, one long ton is 5.0802 × 10^+6 carats. Both figures come from the same defined relation rather than from a measurement, which is why they are the same today as they were in 1959.
Every weight unit here
The whole group — 15 units with their symbols and the size of each one in kilograms — is on the conversion index, along with every pair it makes. The table above already gives each of them relative to a carat.
Cite this page
- APA
- Rule Calculator. (2026). Convert Carats to long tons. Rule Calculator. https://rulecalculators.com/convert/carat-to-long-ton
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- Chicago
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Questions people actually ask
- How many long tons are in a carat?
- 1.9684 × 10^-7. The British ton: 2,240 lb, against the US short ton’s 2,000 and the tonne’s 2,204.62. Three units, one word, and shipping documents use all three.
- How do I convert long tons back to carats?
- Divide by 1.9684 × 10^-7, or multiply by 5.0802 × 10^+6 — they are the same operation.
Other weight conversions
Long tons to carats — the same conversion the other way.