How To Convert Ounces To Grams Calculator

The formula this calculator uses

g = oz x 28.349523125

oz

Mass in avoirdupois ounces - the ounce of body weight, food and parcels

28.349523125

Exact grams per ounce, from 1 oz = 1/16 of 0.45359237 kg

g

Mass in grams

0.03527396194958041

Ounces per gram, the inverse of 28.349523125

How to check the result by hand

1. 1

   Confirm which ounce you have

   The avoirdupois ounce is a mass of 28.349523125 grams, the fluid ounce is a volume, and the troy ounce is a heavier mass of 31.1034768 grams. This page converts the avoirdupois ounce alone, the one used for body weight, food and parcels. If the source is a liquid measure in fluid ounces, or a precious-metal price in troy ounces, the factor here does not apply, so settle the unit before multiplying anything.

2. 2

   Multiply by 28.349523125, using every digit

   The factor is exact, so there is no reason to shorten it to 28.35 or 28. For 8 ounces the calculation is 8 x 28.349523125 = 226.796185 grams. Writing the multiplication with its units attached, ounces x (28.349523125 g / oz), makes the cancellation visible and removes any doubt about whether to multiply or divide, which is the question people hesitate over most often.

3. 3

   Shift the decimal point for kilograms if you need them

   226.796185 grams is 0.226796185 kilograms, because a kilogram is 1000 grams and the metric prefixes are decimal. The same eight ounces is also 0.5 of a pound, since there are sixteen ounces in a pound. Convert once into grams at the start, then move between metric units by shifting the decimal point rather than converting each one from ounces separately.

4. 4

   Round-trip the answer as a check

   Divide the grams by 28.349523125 and confirm you land on the ounces you began with: 226.796185 / 28.349523125 = 8. The check costs one line and catches both errors that matter, applying the factor in the wrong direction and applying it twice. It works cleanly here precisely because the factor is exact, so the round trip closes exactly instead of merely coming close.

5. 5

   Round once, at the end, to a precision the input supports

   A quantity quoted as 8 ounces gives 226.796185 grams, but the defensible answer in a kitchen is about 227 grams, because a round number cannot justify six decimal places. Carry the full factor through every intermediate step and round only when you write the result down. That way rounding never accumulates across a multi-stage calculation, and the precision of the answer matches the precision of the measurement.