Ounces to Grams Converter — oz to g, kg, lb
Convert avoirdupois ounces to grams, kilograms, milligrams and pounds instantly — using the exact international definition with no rounding in the conversion factor itself.
oz
Using the exact avoirdupois factor: 1 oz = 28.349523125 g
- 1
Conversion factor
1 oz = 28.349523125 g = 28.349523125Exact avoirdupois definition: 1 lb = 453.59237 g ÷ 16 oz/lb. - 2
Multiply ounces by factor
8 × 28.349523125 = 226.7962
How does this calculator work?
Grams = ounces × 28.349523125 (exact). Quick lookup: 1 oz = 28.35 g, 4 oz = 113.4 g (¼ lb), 8 oz = 226.8 g (½ lb), 16 oz = 453.6 g (1 lb). The avoirdupois ounce is used for everyday weight; the troy ounce (31.1 g) is for precious metals.
Formula
How this is calculated
The avoirdupois ounce — the standard ounce used in the US and UK for everyday weight — is defined via the international pound: 1 pound = 0.45359237 kg exactly, and 1 pound = 16 ounces exactly. Dividing gives 1 ounce = 0.45359237 ÷ 16 = 0.028349523125 kg = 28.349523125 g. This calculator uses that exact factor, so results are accurate to full floating-point precision.
Note that the avoirdupois ounce is different from the troy ounce (31.1034768 g), which is used for precious metals such as gold and silver. This converter uses the avoirdupois ounce only. Also note that "fluid ounce" is a volume unit (≈ 29.574 mL) and is not the same as the weight ounce converted here.
Common cooking amounts: 1 oz ≈ 28.35 g; 4 oz ≈ 113.4 g (¼ lb); 8 oz ≈ 226.8 g (½ lb); 16 oz ≈ 453.6 g (1 lb).
Frequently asked questions
One avoirdupois ounce equals exactly 28.349523125 grams. This is often rounded to 28.35 g for everyday use, or 28.3 g in casual cooking contexts.
100 grams ÷ 28.349523 = about 3.527 oz. Enter 100 on a scale labeled in grams to get the ounce equivalent, useful for international recipes.
A weight (avoirdupois) ounce is a unit of mass (≈ 28.35 g). A fluid ounce is a unit of volume (≈ 29.574 mL for US fl oz). They are different quantities — 1 fl oz of water happens to weigh about 29.57 g, slightly more than 1 oz by weight.
Also known as
TG we-Calculate Editorial Team. (2026). Ounces to Grams Converter — oz to g, kg, lb [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/ounces-to-grams-converter
TG we-Calculate Editorial Team. "Ounces to Grams Converter — oz to g, kg, lb." TG we-Calculate. 2026. https://we-calculate.com/calculator/ounces-to-grams-converter.
TG we-Calculate Editorial Team, "Ounces to Grams Converter — oz to g, kg, lb," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/ounces-to-grams-converter
@misc{wecalculate_ounces_to_grams_converter, title = {Ounces to Grams Converter — oz to g, kg, lb}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/ounces-to-grams-converter}}, year = {2026}, note = {TG we-Calculate} }
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