How to Convert Tonnes to Carats (t to ct)
Weight units matter at the wet market, where older stalls and Chinese medical halls still quote prices per kati or tael, and when following American recipes in ounces and pounds. This guide shows how to convert tonnes into carats by hand, with examples and a quick-reference table.
The conversion
To convert tonnes to carats, multiply the value by 5,000,000. To go the other way, divide by the same number (or multiply by 2.000000e-07). For a quick estimate, multiply by about 5,000,000.
Carats = tonnes × 5,000,000
Worked examples
- 3 t = 15,000,000 ct
- 12.5 t = 62,500,000 ct
- 75 t = 375,000,000 ct
Tonnes to Carats table
| Tonnes | Carats |
|---|---|
| 1 t | 5,000,000 ct |
| 2 t | 10,000,000 ct |
| 5 t | 25,000,000 ct |
| 10 t | 50,000,000 ct |
| 20 t | 100,000,000 ct |
| 25 t | 125,000,000 ct |
| 50 t | 250,000,000 ct |
| 100 t | 500,000,000 ct |
| 250 t | 1,250,000,000 ct |
| 500 t | 2,500,000,000 ct |
| 1,000 t | 5,000,000,000 ct |
Common questions
Is t to ct exact?
The factors used here are the internationally defined values where they exist; results are rounded for display only.
How do I convert back?
Use the Carats to Tonnes converter.
Mistakes to avoid
Rounding the factor too early
Using 3 instead of 3.28 for feet per metre introduces an error of almost 9% before you have started.
Multiplying when you should divide
Converting to a smaller unit gives a bigger number, and converting to a larger unit gives a smaller one. If your answer moves the wrong way, you have inverted the factor.
Forgetting squared and cubed units
Area and volume factors are the length factor squared or cubed, so 1 m² is about 10.76 sq ft, not 3.28.
Background
Writing the units next to every number while you work is the simplest way to avoid mistakes. If the units do not cancel to leave the one you want, the calculation is set up wrongly.
Unit conversion is simply multiplication by a fixed ratio. The ratio between two units of the same quantity never changes, so once you know it you can convert any value in either direction.
For everyday use, three or four significant figures are usually enough. Engineering, science and trade documents may need more, and rounding should happen only at the end of a calculation.
For any value, use the Tonnes to Carats Converter or browse all weight converters.
Run your own numbers: Tonnes to Carats Converter