⚖️ ct to oz — Carat to Ounce Converter

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

1 unit =
From
To
Formula 1 ct = 0.007054798 oz
Quick Answer — Formula1 ct = 0.007054798 ozMultiply carats by 0.007054798 to get ounces.Reverse: 1 oz = 141.7475 ct
UnitNameValue
0.001 ct7.0548e-06 oz
0.01 ct7.0548e-05 oz
0.1 ct0.00070548 oz
1 ct0.0070548 oz
5 ct0.035274 oz
10 ct0.070548 oz
50 ct0.35274 oz
100 ct0.70548 oz
1000 ct7.0548 oz

About Carat to Ounce 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 ct = 0.007054798 oz

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: Carat to Ounce

A 1-carat diamond solitaire
1 ct = 0.0070548 oz
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 ct = 0.03527399 oz
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 ct = 0.0070548 oz
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 ct = 0.02116439 oz
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.

Carat to Ounce Reference Table

Carat (ct)Ounce (oz)Real-world context
1 ct0.0070548 ozsolitaire diamond
100 ct0.70547981 oz
1000 ct7.0547981 oz
10000 ct70.5479814 oz
100000 ct705.4798 oz

Mental Math Tricks: Carat to Ounce

Divide by 141.7475
Since the factor is small (0.0070548), it's easier to divide: oz value ÷ 141.7475 = ct value.
Use scientific notation
1 ct = 7.05e-03 oz. Count decimal places carefully.
Think in larger units first
Convert to a more familiar unit first, then to oz.

When to Convert Carat to Ounce

💎 Jewellery Design Jewellers specify gemstone weights in carats and metal weights in grams or tola. Converting ct to oz is a core skill in jewellery making.
🏆 Gemstone Grading The 4Cs of diamond grading include carat weight. Converting between ct and oz 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. Carat to Ounce conversion is essential for traders and investors.
⚖️ Hallmarking Precious metal hallmarking authorities certify weights in specific units. Convert between ct and oz 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 ct. Converting to modern oz helps calculate material value accurately.

Frequently Asked Questions — Carat to Ounce

1 carat (ct) equals exactly 0.0070548 ounces (oz). Use the formula: ct × 0.0070548 = oz.

To convert carats to ounces, multiply your value in carats by 0.0070548. For example, 5 ct × 0.0070548 = 0.03527399 oz.

100 carats = 0.70547981 ounces. Calculation: 100 × 0.0070548 = 0.70547981.

To convert ounces back to carats, divide by 0.0070548 (or multiply by 141.7475). Example: 10 oz ÷ 0.0070548 = 1417.475 ct.

Yes. This converter uses the internationally recognised exact conversion factor: 1 ct = 0.0070548 oz. All calculations are performed in your browser with no rounding until display.

10 carats = 0.07054798 ounces. Simply multiply by 0.0070548.

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

Understanding Carat and Ounce

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.

Ounce (oz)

The avoirdupois ounce (oz) equals exactly 28.349523125 grams or 1/16 of an avoirdupois pound. It is widely used in the US and UK for food portions, product packaging, and everyday measurements. Note that the troy ounce (31.1035 g), used for precious metals like gold and silver, is a different and heavier unit than the avoirdupois ounce.

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.

History of the Ounce

The word "ounce" derives from Latin uncia (a twelfth), originally 1/12 of the Roman pound. The avoirdupois ounce developed in medieval England specifically for the wool trade, creating a 16-ounce pound distinct from the Troy 12-ounce pound. The British Imperial system codified the ounce in 1824. The modern exact definition (28.349523125 g) was set by the 1959 International Yard and Pound Agreement.

Interesting fact: A troy ounce (31.1 g) used for gold is heavier than an avoirdupois ounce (28.35 g) used for food — so an "ounce" of gold contains more metal than an "ounce" of flour. A standard large hen's egg weighs approximately 56–63 grams (about 2 oz).