How to Convert Ounces to Carats (oz 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 ounces into carats by hand, with examples and a quick-reference table.
The conversion
To convert ounces to carats, multiply the value by 141.747615625. To go the other way, divide by the same number (or multiply by 0.0070547924). For a quick estimate, multiply by about 140.
Carats = ounces × 141.747615625
Worked examples
- 3 oz = 425.2428 ct
- 12.5 oz = 1,771.85 ct
- 75 oz = 10,631.07 ct
Ounces to Carats table
| Ounces | Carats |
|---|---|
| 1 oz | 141.7476 ct |
| 2 oz | 283.4952 ct |
| 5 oz | 708.7381 ct |
| 10 oz | 1,417.48 ct |
| 20 oz | 2,834.95 ct |
| 25 oz | 3,543.69 ct |
| 50 oz | 7,087.38 ct |
| 100 oz | 14,174.76 ct |
| 250 oz | 35,436.9 ct |
| 500 oz | 70,873.81 ct |
| 1,000 oz | 141,747.62 ct |
Common questions
Is oz 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 Ounces converter.
Mistakes to avoid
Dropping the units
A bare number without a unit is easy to misread later. Always write the unit with the result.
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.
Background
A conversion table is handy for common values, but a calculator is faster and avoids interpolation errors for anything in between.
Many conversion factors are exact by definition. The inch has been defined as exactly 2.54 centimetres since 1959, and the pound as exactly 0.45359237 kilograms, so conversions involving them can be as precise as you need.
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 Ounces to Carats Converter or browse all weight converters.
Run your own numbers: Ounces to Carats Converter