Tonnes to Carats
Type a value in either box to convert between tonnes and carats. The factor is 5e+06.
| Tonnes | Carats |
|---|---|
| 1 t | 5000000 ct |
| 2 t | 10000000 ct |
| 3 t | 15000000 ct |
| 5 t | 25000000 ct |
| 10 t | 50000000 ct |
| 25 t | 125000000 ct |
| 50 t | 250000000 ct |
| 100 t | 500000000 ct |
How to use
- Enter a value in the Tonnes field.
- The Carats figure appears immediately — no button to press.
- Typing in the Carats field converts back to Tonnes the same way.
- Use the reference table for the values that come up most often.
Tonnes to Carats formula
The factor from tonnes to carats is 5000000.
ct = t × 5000000
Why this factor: the tonne and the carat are both defined against the kilogram, so dividing one definition by the other gives 5000000 directly. Both definitions are set out in full below.
To go the other way, divide by 5000000 — or use the Carats to Tonnes converter, which is the same calculation reversed.
Worked example
Start with 150 t. Multiply by 5000000 to get 750000000 ct.
150 t × 5000000 = 750000000 ct
The converter above does this for any value you type, in either direction.
What is a tonne?
A tonne, or metric ton, is 1,000 kilograms — the standard unit for bulk freight and industrial quantities.
Definition: Exactly 1,000 kilograms. Accepted for use with SI but not itself an SI unit.
Where it is used: Shipping and freight, steel and cement output, vehicle masses, and carbon emissions accounting.
Worth knowing: Distinct from the US short ton (2,000 lb ≈ 907 kg) and the UK long ton (2,240 lb ≈ 1,016 kg).
What is a carat?
A metric carat is the standard mass unit for gemstones.
Definition: Exactly 200 milligrams — that is, 0.2 gram — standardized internationally in 1907.
Where it is used: Diamond and gemstone weight throughout the jewellery trade.
Worth knowing: Do not confuse the carat (gemstone mass) with the karat (gold purity out of 24). A 1-carat diamond and 24-karat gold measure entirely different things.
Tonnes vs Carats
The tonne is a metric unit while the carat is a specialized unit. That is why the factor between them is not a round number: the two systems were defined independently and only later tied together by exact agreement.
Frequently asked questions
How many carats are in a tonne?
One tonne equals 5000000 carats.
What is the formula to convert tonnes to carats?
Multiply the number of tonnes by 5000000. To reverse it, divide by 5000000 instead.
How do I convert carats back to tonnes?
Divide by 5000000, which is the same as multiplying by 2e-07.
How many carats are in 10 tonnes?
10 t works out to 50000000 ct.
Is there anything to watch out for with tonnes?
Distinct from the US short ton (2,000 lb ≈ 907 kg) and the UK long ton (2,240 lb ≈ 1,016 kg).
How is the tonne defined?
Exactly 1,000 kilograms. Accepted for use with SI but not itself an SI unit.