HomeMath › Grams to Ounces Converter

Grams to Ounces Converter

Convert grams to avoirdupois ounces with the exact NIST factor. Enter any gram amount and get ounces, decimal pounds, and a pounds-and-ounces readout for scales that speak imperial.

Example: with Weight in grams 100 → Ounces: 3.53 oz.

  • Pounds and ounces0 lb 3.5 oz
  • In decimal pounds0.22 lb

Computed by the calculator below using its default values. Change any input to see your own numbers.

Ounces
Pounds and ounces
In decimal pounds

oz = g ÷ 28.349523125. The factor is exact: one avoirdupois pound is defined as 453.59237 g, and an ounce is one sixteenth of that.

The one number to remember: 28.35

One avoirdupois ounce is exactly 28.349523125 grams — that is not a measurement but a definition, fixed by the 1959 international agreement that set the pound at 453.59237 grams. Divide any gram weight by 28.3495 and you have ounces; divide by 453.59237 and you have pounds. A 100 g portion is 3.53 oz, and a 500 g package is 17.64 oz, or just over a pound.

The rough shortcut of calling an ounce 30 grams is fine for a handful of nuts but drifts fast: at 500 g it claims 16.7 oz when the true answer is 17.6. Recipes translated between metric and US cookbooks usually round to the nearest 5 g, which is why 1 oz appears as 28 g or 30 g depending on the book.

How it’s calculated

Ounces = grams ÷ 28.349523125; pounds = grams ÷ 453.59237. Both factors are exact NIST definitions (1 lb = 453.59237 g; 1 oz = 1/16 lb). The pounds-and-ounces line shows whole pounds with the remainder rounded to 0.1 oz.

Converts avoirdupois (everyday) ounces only — troy ounces for precious metals are heavier at 31.1035 g, and fluid ounces are volume, not weight.

Grams to ounces quick reference

GramsOuncesHandy anchor
10 g0.35 oztwo US quarters
28.35 g1.00 ozone ounce exactly
50 g1.76 ozmedium egg
100 g3.53 ozstick of butter is 113 g
250 g8.82 ozmetric half pound
500 g17.64 ozjust over 1 lb
1,000 g35.27 oz2 lb 3.3 oz

Computed with 1 oz = 28.349523125 g (NIST exact); rounded to two decimals.

Common mistakes

  • Dividing by 30 instead of 28.35 — a 5 percent error that compounds on larger weights.
  • Reading fluid ounces on a liquid measuring cup as if they were scale ounces.
  • Using this factor for gold or silver, which trade in troy ounces of 31.1035 g.
  • Rounding 1 oz to 28 g in a bread formula, where a few grams of yeast or salt actually matter.

Frequently asked questions

What is the formula for grams to ounces?

Ounces = grams ÷ 28.349523125. The divisor is exact because the pound is defined as 453.59237 grams and an ounce is one sixteenth of a pound. So 100 g = 3.53 oz.

How many grams are in an ounce?

Exactly 28.349523125 grams in an avoirdupois ounce — 28.35 g for everyday purposes. A troy ounce, used for precious metals, is different at 31.1035 g.

Is 500 grams more than a pound?

Yes, slightly. A pound is 453.59 g, so 500 g is about 1.1 lb, or 1 lb 1.6 oz. That is why metric recipes often treat 500 g as a generous pound.

Are these the same ounces as fluid ounces?

No. This converter handles weight ounces measured on a scale. Fluid ounces measure volume (29.5735 mL each), and the gram weight of a fluid ounce depends on the substance's density.