Ounces to Grams Converter: Fast, Accurate, and Easy-to-Use

The math behind the conversion

One avoirdupois ounce (the standard "weight" ounce used for food and postage) equals 28.3495231 grams. This calculator rounds that to 28.35 and multiplies your input by it, which is accurate enough for kitchen and shipping use but not for lab-grade precision. Enter 8 and the tool returns 8 × 28.35 = 226.80 grams — roughly the weight of a standard block of cheddar.

How much does the rounding matter?

At 16 ounces (1 lb), the exact figure is 453.592 g; this tool's rounded factor gives 453.60 g — an error of 0.008 g, or about 0.002%. That's irrelevant for a recipe or a package weight, but if you need scientific precision, use the exact factor 28.3495231 instead of the rounded one.

Weight ounces vs. fluid ounces

This converter handles mass (avoirdupois ounces), not volume. A fluid ounce of water weighs about 29.57 g because it's a unit of volume, not weight — the two only line up for substances with a density close to water's. Don't use this tool to convert fluid ounces of milk or oil; that requires a density-specific calculation, not a straight multiplication.

Common reference points

1 oz = 28.35 g, 4 oz = 113.40 g, 8 oz = 226.80 g, 16 oz (1 lb) = 453.60 g. These are the values you'll get back from the tool for round-number inputs, useful for sanity-checking a result at a glance.