⚖️ g to ct — Gram to Carat Converter

Convert weight and mass units — kilograms, pounds, grams, ounces, tons, carats and more.

1 unit =
From
To
Formula 1 g = 5 ct
Quick Answer — Formula1 g = 5 ctMultiply grams by 5 to get carats.Reverse: 1 ct = 0.2 g
UnitNameValue
0.001 g0.005 ct
0.01 g0.05 ct
0.1 g0.5 ct
1 g5 ct
5 g25 ct
10 g50 ct
50 g250 ct
100 g500 ct
1000 g5000 ct

About Gram to Carat Conversion

The Milligram (mg) and the Gram (g) are both units of weight & mass. Converting between them is straightforward using the formula above.

Formula: 1 g = 5 ct

This converter uses internationally recognized conversion factors. All calculations are performed client-side in your browser — no data is sent to any server.

Worked Examples: Gram to Carat

A 1-carat diamond solitaire
1 g = 5 ct
The classic engagement ring stone is a 1-carat diamond = 0.2 g. Jewellers worldwide quote gemstone weight in carats and fractions of carats.
A large gemstone
5 g = 25 ct
A 5-carat ruby is considered a fine specimen — it weighs just 1 gram, showing how small even prestigious gemstones truly are.
A tola of gold bar
1 g = 5 ct
A 1-tola gold bar (≈11.66 g) is the most common retail gold investment unit across India, Pakistan, and UAE.
A gem-quality sapphire
3 g = 15 ct
A 3-carat blue sapphire weighs 0.6 g. The per-carat price of fine sapphires can exceed $10,000, so precise weight measurement is critical.

Gram to Carat Reference Table

Gram (g)Carat (ct)Real-world context
1 g5 ctlarge paperclip
5 g25 ct
10 g50 ct
50 g250 ct
100 g500 ctsmall apple

Mental Math Tricks: Gram to Carat

Multiply by 5
1 g = 5 ct exactly. 2 g = 10 ct; 10 g = 50 ct; 100 g = 500 ct.
Move decimal and multiply
g × 5 = ct. For 0.5 g: 0.5 × 5 = 2.5 ct.
Reverse of the 5-carat rule
Since 5 ct = 1 g, every gram = 5 carats.

When to Convert Gram to Carat

💎 Jewellery Design Jewellers specify gemstone weights in carats and metal weights in grams or tola. Converting g to ct is a core skill in jewellery making.
🏆 Gemstone Grading The 4Cs of diamond grading include carat weight. Converting between g and ct helps compare stones across different grading systems.
💰 Gold Trading Gold prices are quoted per gram, per tola, and per troy ounce depending on the market. Gram to Carat conversion is essential for traders and investors.
⚖️ Hallmarking Precious metal hallmarking authorities certify weights in specific units. Convert between g and ct for compliance and documentation.
🎯 Archery & Ballistics Arrow and bullet weights are specified in grains. Converting to grams or vice versa is routine for archers and competitive shooters.
🏛️ Antique Appraisal Historical weights for silver and gold artefacts may be recorded in g. Converting to modern ct helps calculate material value accurately.

Frequently Asked Questions — Gram to Carat

1 gram (g) equals exactly 5 carats (ct). Use the formula: g × 5 = ct.

To convert grams to carats, multiply your value in grams by 5. For example, 5 g × 5 = 25 ct.

100 grams = 500 carats. Calculation: 100 × 5 = 500.

To convert carats back to grams, divide by 5 (or multiply by 0.2). Example: 10 ct ÷ 5 = 2 g.

Yes. This converter uses the internationally recognised exact conversion factor: 1 g = 5 ct. All calculations are performed in your browser with no rounding until display.

10 grams = 50 carats. Simply multiply by 5.

Converting grams to carats is commonly needed for jewellery valuation, gemstone trading, precious metal buying and selling, and hallmarking compliance where one system uses g and another uses ct.

Understanding Gram and Carat

Gram (g)

The gram (g) is a unit of mass in the metric system equal to one-thousandth of a kilogram (0.001 kg). While the kilogram is the SI base unit, the gram is the practical everyday unit for small masses in cooking, pharmacy, chemistry, and nutrition labelling. The word derives from Late Latin gramma (small weight), itself from Greek.

Carat (ct)

The metric carat (ct) is the unit of mass used worldwide for gemstones and pearls, equal to exactly 200 milligrams (0.2 g). It is distinct from "karat" (K), the measure of gold purity (24K = 100% gold). A 1-carat diamond weighs exactly 0.2 g; the famous 45.52-carat Hope Diamond weighs approximately 9.1 g.

History of the Gram

Defined in 1795 by the French Academy of Sciences as the mass of one cubic centimetre of pure water at 4 °C — this made 1 mL of water weigh almost exactly 1 gram. The gram was the practical base of early metric calculations before the kilogram took over as SI base unit in 1875. The relationship 1 mL water ≈ 1 g is still a useful approximation in cooking and chemistry.

Interesting fact: A standard large paperclip weighs about 1 gram. The gram forms the basis for milligram (mg), microgram (μg), and tonne (10⁶ g) through SI prefixes.

History of the Carat

The word "carat" derives from Greek keration (κεράτιον), meaning carob pod. Carob seeds were believed to have remarkably uniform weight and were used as counterweights for balancing precious stones. The carat value varied across countries (0.187–0.216 g) until the Fourth General Conference on Weights and Measures standardised the metric carat at exactly 200 mg in 1907. Most countries adopted the metric carat between 1914 and 1930.

Interesting fact: The largest gem-quality diamond ever found, the Cullinan Diamond (1905), weighed 3,106.75 carats (621.35 g) before being cut into 9 major and 96 minor stones, two of which are in the British Crown Jewels.