Carat to Kilogram Converter

Weight · unit-converter

Convert Carat to Kilogram with a fixed input and output unit, step-by-step formula line, and reference tables. All calculations use gram-based factors (international avoirdupois pound and metric definitions). The full Weight Converter also includes carat, grain, and US/UK hundredweight.

Calculator

From: Carat (ct)

To: Kilogram (kg)

About Carat

The metric carat is exactly 0.2 grams (200 mg), commonly used for gemstones and jewelry.

About Kilogram

The kilogram is the SI base unit of mass (defined via fundamental constants). Everyday metric weights and science use kilograms and grams.

How to convert carats to kilograms

1 carat is equal to 0.0002 kilogram:

1 ct = (0.2 g ÷ 1000 g) kg = 0.0002 kg

Each carat is defined as 0.2 g and each kilogram as 1000 g, so one ct equals 0.2 ÷ 1000 kg = 0.0002 kg.

Let w(ct) be the numeric value of the same mass measured in Carat (ct), and w(kg) the value in Kilogram (kg). Then:

w(kg) = w(ct) × (0.2 / 1000)

Equivalently, divide by how many ct fit into one kg (grams per kg divided by grams per ct):

w(kg) = w(ct) ÷ 5000

Or: kilogram = carat ÷ 5000

Examples

Example #1: Convert 20 ct to kilogram

20 ct = 20 ct × (0.2/1000) kg = 0.004 kg

20 ct = 20 ct ÷ 5000 = 0.004 kg

Example #2: Convert 50 ct to kilogram

50 ct = 50 ct × (0.2/1000) kg = 0.01 kg

50 ct = 50 ct ÷ 5000 = 0.01 kg

Summary

To convert Carat to Kilogram, multiply the value in ct by the ratio of grams per ct divided by grams per kg. Equivalently: value_kg = value_ct × (0.2 / 1000). Numerically, 1 ct equals 0.0002 kg.

Relationship context

Both units are metric (SI) and tied to the gram via the kilogram. Conversions use exact ratios from their gram definitions. The factor from Carat to Kilogram is 2.000000e-4 (1 ct = 0.0002 kg).

Conversion tables

Carat (ct)Kilogram (kg)
0.10.00002
10.0002
20.0004
30.0006
40.0008
50.001
60.0012
70.0014
80.0016
90.0018
Carat (ct)Kilogram (kg)
100.002
200.004
300.006
400.008
500.01
600.012
700.014
800.016
900.018
1000.02