How to Convert Carats to Pounds (ct to lb)
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 carats into pounds by hand, with examples and a quick-reference table.
The conversion
To convert carats to pounds, multiply the value by 0.0004409245. To go the other way, divide by the same number (or multiply by 2,267.96185). Because the factor is tiny, scientific notation keeps the numbers manageable.
Pounds = carats × 0.0004409245
Worked examples
- 3 ct = 0.001323 lb
- 12.5 ct = 0.005512 lb
- 75 ct = 0.033069 lb
Carats to Pounds table
| Carats | Pounds |
|---|---|
| 1 ct | 0.000441 lb |
| 2 ct | 0.000882 lb |
| 5 ct | 0.002205 lb |
| 10 ct | 0.004409 lb |
| 20 ct | 0.008818 lb |
| 25 ct | 0.011023 lb |
| 50 ct | 0.022046 lb |
| 100 ct | 0.044092 lb |
| 250 ct | 0.110231 lb |
| 500 ct | 0.220462 lb |
| 1,000 ct | 0.440925 lb |
Common questions
Is ct to lb 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 Pounds to Carats 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.
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.
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.
Background
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.
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.
For any value, use the Carats to Pounds Converter or browse all weight converters.
Run your own numbers: Carats to Pounds Converter