Convert Ounce to Gram
Conversion Formula
g = oz × 28.3495To convert Ounce to Gram, use the formula above. This is the standard conversion factor used worldwide.
Conversion Table
| Ounce (oz) | Gram (g) |
|---|---|
| 1 | 28.3495 |
| 8 | 226.7960 |
| 16 | 453.5920 |
| 32 | 907.1840 |
Why convert Ounce to Gram
A US recipe lists ingredients in ounces, and a cook using a scale that only displays grams, or following an international baking video that expects metric weights, needs the gram figure instead. It runs opposite to the more common gram to ounce lookup, and it comes up constantly in baking, where gram precision genuinely changes how a recipe turns out.
Where the number comes from
This page uses the avoirdupois ounce, the standard food and retail ounce, at exactly 28.349523125 grams. That is distinct from the troy ounce (31.1034768 g) used for precious metals, so converting a jewelry or bullion weight given in troy ounces with this factor will understate the true gram weight.
Quick reference
| 1 oz | 28.3495 g | avoirdupois, exact ratio 28.349523125 |
| 4 oz | 113.4 g | a common recipe measure, a quarter pound |
| 8 oz | 226.8 g | half a pound |
| 16 oz (1 lb) | 453.59 g | |
| 1 troy oz | 31.1035 g | used for gold and silver, not this page's default |
| 0.5 oz | 14.17 g | a common postage weight tier |
Common mistakes
- Baking recipes that mix volume ounces (fluid ounces, for liquids) and weight ounces (for dry ingredients like flour) in the same ingredient list cause real confusion when converting to grams, since a fluid ounce of water and a weight ounce of flour are not the same quantity and do not convert with the same factor.
- Postage and shipping weights are another trap: a package rated in ounces on a US label needs the avoirdupois factor, not the troy one, even though the word 'ounce' alone doesn't say which.
Frequently Asked Questions
How do I convert a US recipe listed in ounces to grams for a metric scale?
Multiply the ounce figure by 28.349523125, or 28.35 for practical purposes. Most baking scales let you switch the display unit directly, which avoids doing the math by hand.
Is 8 oz of flour the same weight as 8 oz of water?
Yes, weight ounces measure mass regardless of what is being weighed, so 8 oz of flour and 8 oz of water both convert to 226.8 g. What differs is the volume each occupies, since flour is far less dense than water.
Why does my scale show a slightly different gram figure than my calculator?
Most kitchen scales round to the nearest gram or half gram for display, while a calculator carries the full 28.349523125 factor, so small rounding differences of a gram or less are normal and do not affect a recipe.
How do I convert an ounce weight of gold or silver to grams?
Use the troy ounce factor of 31.1034768 g, not the avoirdupois factor this page defaults to, since precious metals are weighed and priced on the troy system.