How to Convert Milligrams to Carats (mg 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 milligrams into carats by hand, with examples and a quick-reference table.
The conversion
To convert milligrams to carats, multiply the value by 0.005. To go the other way, divide by the same number (or multiply by 200). For a quick estimate, multiply by about 0.005.
Carats = milligrams × 0.005
Worked examples
- 3 mg = 0.015 ct
- 12.5 mg = 0.0625 ct
- 75 mg = 0.375 ct
Milligrams to Carats table
| Milligrams | Carats |
|---|---|
| 1 mg | 0.005 ct |
| 2 mg | 0.01 ct |
| 5 mg | 0.025 ct |
| 10 mg | 0.05 ct |
| 20 mg | 0.1 ct |
| 25 mg | 0.125 ct |
| 50 mg | 0.25 ct |
| 100 mg | 0.5 ct |
| 250 mg | 1.25 ct |
| 500 mg | 2.5 ct |
| 1,000 mg | 5 ct |
Common questions
Is mg 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 Milligrams converter.
Mistakes to avoid
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.
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.
Mixing similar-sounding units
US and imperial gallons, pints and tons are different sizes, and decimal kilobytes differ from binary kibibytes.
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.
A conversion table is handy for common values, but a calculator is faster and avoids interpolation errors for anything in between.
For any value, use the Milligrams to Carats Converter or browse all weight converters.
Run your own numbers: Milligrams to Carats Converter