Grams of mayonnaise to fluid ounces runs on one number, 0.036363636 fluid ounces per gram. It is a measured property of this ingredient rather than a defined conversion, which is why a generic volume-to-weight tool cannot give you it.
The density behind that figure is 0.92989 g per mL, against 1.00 for water. A cup of water weighs 236.6 g and a cup of mayonnaise weighs 220 g, so this ingredient is 92.99% as heavy as the same volume of water — the single fact the whole page rests on.
This is the pair that catches people out. A fluid ounce is a volume and an ounce is a weight, and they are only the same number for something with the density of water. One fluid ounce of mayonnaise weighs 0.97 oz, so the two readings differ by 3% — worth knowing before trusting a recipe that just says "oz".
Grams are the unit this conversion is really for. A domestic scale resolves to a gram, which is 0.455% of a cup of mayonnaise, so weighing gets an accuracy no measuring cup can reach. A 500 g pack of it is 2.273 cups, and a 1 kg pack 4.545.
What the number depends on: An emulsion of oil in egg, so it is lighter per cup than the water-based sauces sitting next to it in the fridge.
The formula
grams- The amount of mayonnaise you are converting, in grams
0.0363636363636- Fluid Ounces per gram for mayonnaise, from its density of 0.92989 g/mL
fluid ounces- The equivalent quantity in fluid ounces
How it works, step by step
- Enter the quantity in grams.
- It is multiplied by 0.0363636363636, the fluid ounces-per-gram figure for mayonnaise.
- The result appears in fluid ounces, with a second reading in mL beneath it.
- Use the measure table if you want a standard recipe quantity rather than a number you type in.
Worked examples
50 g of mayonnaise in fluid ounces
A recipe calling for 50 g of mayonnaise needs 1.81818 fluid ounces on the scale. The arithmetic is 50 × 0.036363636 = 1.8181818, and halving the recipe halves the weight to 0.909091 fluid ounces.
150 g of mayonnaise in fluid ounces
A recipe calling for 150 g of mayonnaise needs 5.45455 fluid ounces on the scale. The arithmetic is 150 × 0.036363636 = 5.4545455, and halving the recipe halves the weight to 2.72727 fluid ounces.
500 g of mayonnaise in fluid ounces
500 g of mayonnaise weighs out at 18.1818 fluid ounces. Divide 18.1818 by 0.036363636 and you get back to 500 g, which is the quickest check that the factor is the right way up.
How to read your score
Frequently asked questions
How many fluid ounces are in 1 g of mayonnaise?
One gram of mayonnaise is 0.036363636 fluid ounces. Half that quantity is 0.0181818 fluid ounces and double it is 0.0727273 fluid ounces, so the figure scales straight up and down — there is no offset in this conversion, only the factor.
Why is a cup of mayonnaise not 236 g like water?
Because weight per cup depends on what is in the cup. Mayonnaise has a density of 0.92989 g per mL where water has 1.00, so a cup of it weighs 220 g rather than 236.6 g. That is a difference of 16.6 g per cup, and it is the reason a single volume-to-weight factor cannot be applied to every ingredient.
Does how I measure it change the weight?
Barely. Mayonnaise does not compress, so a cup of it is 220 g however it is poured — within about 1%, which is inside the accuracy of a domestic scale. This is the group where measuring by volume is defensible.
Is a fluid ounce of mayonnaise the same as an ounce?
No. A fluid ounce is a volume — one eighth of a US cup, 29.57 mL — and an ounce is a weight. One fluid ounce of mayonnaise weighs 0.97 oz, so the two readings differ by 3%. They coincide only for something with the density of water, and then only roughly.
Is this a US cup or a metric cup?
US customary: 236.59 mL, which is the cup every US recipe means. A metric cup is 250 mL, so the same cup of mayonnaise would weigh 232.47 g instead of 220 g — 12.5 g more, or 5.67%. Australian and some European recipes use the metric cup, and the difference is large enough to matter in baking.
Do I need a scale for this, or will measuring cups do?
A scale, if the result matters. Volume measuring carries a spread of about 1% for mayonnaise — roughly 2.2 g on a 220 g cup — while a domestic scale is accurate to a gram or two. For anything where the ratio of ingredients drives the outcome, bread and pastry above all, weigh it.
How much does 3 fl oz of mayonnaise weigh?
3 fl oz of mayonnaise comes to 82.5 g, or 82.5 grams. This page runs that calculation in reverse — enter a weight and it returns the volume — and the fluid-ounces-to-grams page does it in the direction the question is usually asked.
Mayonnaise in grams and fluid ounces
| Grams | Fluid Ounces | Unrounded |
|---|---|---|
| 5 g | 0.181818 fl oz | 0.1818181818 |
| 10 g | 0.363636 fl oz | 0.3636363636 |
| 25 g | 0.909091 fl oz | 0.9090909091 |
| 50 g | 1.81818 fl oz | 1.818181818 |
| 100 g | 3.63636 fl oz | 3.636363636 |
| 125 g | 4.54545 fl oz | 4.545454545 |
| 150 g | 5.45455 fl oz | 5.454545455 |
| 200 g | 7.27273 fl oz | 7.272727273 |
| 250 g | 9.09091 fl oz | 9.090909091 |
| 300 g | 10.9091 fl oz | 10.90909091 |
| 500 g | 18.1818 fl oz | 18.18181818 |
| 1000 g | 36.3636 fl oz | 36.36363636 |
Based on 220 g per cup of mayonnaise. One gram of mayonnaise is 0.036363636 fluid ounces.
| Measure | Grams | Ounces | Millilitres |
|---|---|---|---|
| 1 cup | 220 g | 7.76 oz | 236.6 mL |
| 3/4 cup | 165 g | 5.82 oz | 177.4 mL |
| 2/3 cup | 146.7 g | 5.17 oz | 157.7 mL |
| 1/2 cup | 110 g | 3.88 oz | 118.3 mL |
| 1/3 cup | 73.33 g | 2.59 oz | 78.86 mL |
| 1/4 cup | 55 g | 1.94 oz | 59.15 mL |
| 1 tbsp | 13.75 g | 0.485 oz | 14.79 mL |
| 1 tsp | 4.583 g | 0.162 oz | 4.929 mL |
US customary measures: 1 cup = 236.59 mL, 1 tbsp = 14.79 mL, 1 tsp = 4.93 mL.
| Ingredient | Grams per cup | Ounces per cup | Density (g/mL) |
|---|---|---|---|
| Olive oil | 216 g | 7.619 oz | 0.913 |
| Vegetable oil | 218 g | 7.69 oz | 0.9214 |
| Coconut oil | 218 g | 7.69 oz | 0.9214 |
| Mayonnaise (this page) | 220 g | 7.76 oz | 0.9299 |
| Cream cheese | 227 g | 8.007 oz | 0.9595 |
| Water | 236 g | 8.325 oz | 0.9975 |
| Heavy cream | 238 g | 8.395 oz | 1.006 |
Ordered by weight. The spread across this group is why a single generic cups-to-grams factor cannot work.