Grams measure weight and fluid ounces measure volume — converting between them depends on the liquid’s density, not a fixed ratio.
How it works
Grams are first converted to milliliters using the liquid’s density, then divided by 29.5735 (mL per US fluid ounce) to get fluid ounces. The default density is water’s.
What this does not include
This does not include a built-in density lookup for specific liquids — check a reliable source for the exact density of whatever liquid you’re measuring if it isn’t water.
How to use this calculator
- Enter the grams and the liquid’s density (defaults to water).
Frequently asked questions
Why does water default to exactly 1 g/mL?
Because 1 milliliter of water weighs almost exactly 1 gram at standard conditions — a widely used, convenient reference point.
Is a US fluid ounce the same as a UK fluid ounce?
No — a UK/imperial fluid ounce is a slightly different size than the US fluid ounce used in this calculator.
Where is this conversion most commonly needed?
Comparing a US-recipe fluid ounce measurement against an ingredient’s metric weight listed on packaging.
