This converter turns tonnes into carats instantly, using the exact factor 1 tonne = 5000000 carats. Type any number and the result updates as you go — nothing is sent to a server, so the arithmetic happens entirely in your browser.
The metric ton: exactly 1,000 kilograms, used for freight and vehicle mass. Exactly 200 milligrams — the mass unit for gemstones and pearls.
Because the relationship is a simple proportion, one multiplication does the whole job. The table further down gives pre-computed values for the amounts people look up most often, and the result panel also reports the reverse conversion so you can check the figure both ways.
The formula
tonnes- The amount you are converting, measured in tonnes
5000000- The exact number of carats in one tonne
carats- The converted result
How it works, step by step
- Enter the number of tonnes you want to convert.
- The value is multiplied by 5000000, the exact conversion factor.
- The result is displayed in carats, rounded for readability.
- The unrounded value and the reverse conversion appear underneath so you can verify it.
Worked examples
Converting 5 tonnes
Multiply 5 by 5000000. That gives 25,000,000 carats. A quick sanity check: one tonne is larger than one carat, so the number should get bigger — and it does.
Converting 72 tonnes
72 × 5000000 = 360,000,000 carats. Working backwards, 360,000,000 ÷ 5000000 returns 72 tonnes, which confirms the factor is applied the right way round.
How to read your score
Frequently asked questions
How many carats are in one tonne?
Exactly 5000000. Every conversion on this page is that single number multiplied by your input, so the result carries no rounding error beyond what is shown.
What is the formula to convert tonnes to carats?
Carats = tonnes × 5000000. To reverse it, divide instead: tonnes = carats ÷ 5000000, which is the same as multiplying by 2e-07.
Is the tonne bigger than the carat?
Yes. One tonne equals 5e+06 carats, so it is the larger unit.
Why does my answer differ slightly from other tonnes to carats converters?
Most differences come from rounding the factor too early. This tool keeps full double precision through the calculation and only rounds at the final display step, and it also shows the unrounded value so you can see exactly where any difference appears.
What is a tonne?
The metric ton: exactly 1,000 kilograms, used for freight and vehicle mass.
What is a carat?
Exactly 200 milligrams — the mass unit for gemstones and pearls.
Tonnes to carats reference table
| Tonnes | Carats |
|---|---|
| 0.5 t | 2,500,000 ct |
| 1 t | 5,000,000 ct |
| 2 t | 10,000,000 ct |
| 3 t | 15,000,000 ct |
| 5 t | 25,000,000 ct |
| 10 t | 50,000,000 ct |
| 15 t | 75,000,000 ct |
| 20 t | 100,000,000 ct |
| 25 t | 125,000,000 ct |
| 50 t | 250,000,000 ct |
| 75 t | 375,000,000 ct |
| 100 t | 500,000,000 ct |
| 250 t | 1,250,000,000 ct |
| 500 t | 2,500,000,000 ct |
| 1000 t | 5,000,000,000 ct |
Exact factor: 1 tonne = 5000000 carats. Values rounded for display.