Convert Ounce to Gram (ozg)

The ounce is the standard small-weight unit in American kitchens, postage, and precious-metal trading.

28.349523
1 oz28.349523 gNIST · BIPM accuracy

Ounce to Gram Conversion Table

10 common values
OunceGram
1 oz28.349523 g
5 oz141.74762 g
10 oz283.49523 g
25 oz708.73808 g
50 oz1,417.4762 g
100 oz2,834.9523 g
250 oz7,087.3808 g
500 oz14,174.762 g
1,000 oz28,349.523 g
5,000 oz141,747.62 g

How to Convert Ounce to Gram Manually

Step by Step

Converting ounces to grams is straightforward: multiply by the conversion factor. Follow these three steps to do it by hand or in your head.

  1. 1
    Take your value in ounces
    Start with the number of ounces (oz) you want to convert.
  2. 2
    Multiply by 28.349523
    The conversion factor from oz to g is 28.349523. Multiply your value by this number.
  3. 3
    Read the result in grams
    The result is your value in grams (g).
Practical Examples
1 oz
equals
28.349523 g
5 oz
equals
141.74762 g
10 oz
equals
283.49523 g
25 oz
equals
708.73808 g
100 oz
equals
2,834.9523 g

Formula

Multiply the value in ounces by 28.349523. For the reverse direction, multiply by 0.035274.

Forwardg = oz × 28.349523
Reverseoz = g × 0.035274
Example: 10 oz × 28.349523 = 283.49523 g

Tips

Use these in everyday conversions
  • 1 oz = 28.35 g exactly (avoirdupois); 1 troy oz = 31.10 g.
  • 16 oz = 1 lb in the avoirdupois system used for food.
  • When converting a US recipe, 1 oz ≈ 2 tablespoons of a liquid ingredient.

Common Mistakes

Avoid these
  • Confusing mass ounces (28.35 g) with fluid ounces (volume).
  • Using avoirdupois ounces (28.35 g) for precious-metal pricing — gold is in troy ounces (31.10 g).
  • Multiplying lb × 16 and calling the result oz — correct only for weight, not volume.

About Ounce and Gram

What is the Ounce?

The ounce equals exactly 28.349523125 grams or 1/16 of a pound. The word derives from the Latin 'uncia,' meaning one twelfth (the original Roman ounce was 1/12 of a Roman pound). The modern avoirdupois ounce, used for everyday weights in the United States and the United Kingdom, replaced the older Tower and Troy systems. It is the standard unit for American kitchen recipes (where 'ounce' refers to weight, distinct from the fluid ounce of volume), postal rates, package sizes (a 12-oz can of soda), and boxing-glove weights. Precious metals like gold and silver use the troy ounce (31.103 g), about 10% heavier than the avoirdupois ounce. The ounce relates to the pound (16 oz = 1 lb), the gram (1 oz ≈ 28.35 g), and the grain (1 oz = 437.5 grains).

  • American and British cooking recipes
  • Food packaging in the US
  • Precious metals (troy ounce = 31.10 g, different from avoirdupois)
Real-world examples

A US tin of tuna is 5 oz (142 g). A Starbucks grande coffee is 16 fl oz (473 ml). Gold is traded in troy ounces (31.10 g).

What is the Gram?

The gram equals one thousandth of a kilogram (0.001 kg) and is the everyday metric unit for cooking ingredients, postage, jewelry, pharmaceuticals, and small product weights. Originally defined in 1795 as 'the absolute weight of a volume of pure water equal to a cube of one hundredth of a meter at the temperature of melting ice,' the gram is now formally defined via the kilogram. It relates simply to the milligram (1,000 mg = 1 g) and the kilogram (1,000 g = 1 kg). European nutrition labels universally use grams for ingredient quantities, and recipes worldwide outside North America measure ingredients by mass in grams rather than by volume. Gold and silver are traded in grams for small quantities, while gemstones use carats (0.2 g = 1 carat). A standard paper clip weighs about 1 g.

  • European cooking and baking recipes
  • Over-the-counter medication dosages
  • Gold, silver and gemstone retail (per gram pricing)
Real-world examples

A chicken egg weighs about 60 g. A standard bar of chocolate is 100 g. A euro coin weighs 7.5 g.

Learn About Both Units

⚖️ Reference

What is the Ounce?

Read the unit page →
⚖️ Reference

What is the Gram?

Read the unit page →

Ounce to Gram FAQ

5 questions
How many grams in a ounce?
One ounce equals 28.349523 grams.
How do I convert ounces to grams?
Multiply the ounce value by 28.349523 to get the equivalent in grams.
What is 100 ounces in grams?
100 ounces equals 2,834.9523 grams.
Is a ounce bigger than a gram?
Yes. 1 ounce equals 28.349523 grams, so one ounce is larger.
How to convert ounces to grams without a calculator?
Multiply by 28.35 for a quick estimate; use a calculator for precise results.

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