A cup of mayonnaise is 220 g — the USDA figure, measured spooned and levelled. Emulsified oil, egg and vinegar spread. It is used for sandwiches, dressings, dips and coleslaw. It is one of the heaviest spreads in the kitchen at 220 g per cup, because it is mostly oil, and that density is the first thing to know: a cup of mayonnaise is a serious amount of fat, which is why it makes a coleslaw creamy and a sandwich rich, and why the amount you use decides whether a dish is balanced or greasy. This guide covers the weight of mayonnaise in every measure you will use — cups, tablespoons and teaspoons — how to measure it correctly, what to use instead when you run out, and how to store it. All weights on this page are approximate; verify with a kitchen scale when the recipe matters.
Mayonnaise: weight and measurement table
The table below gives the weight of Mayonnaise in every measure you will use, from a teaspoon up to 2 cups, all derived from the USDA figure of 220 g per cup, spooned and levelled. Every figure is approximate — spooned and levelled is a technique, not a machine setting — so when the recipe matters, weigh the ingredient on a kitchen scale instead.
| Amount | Weight (approx.) |
|---|---|
| 1 teaspoon | 4.6 g |
| 1 tablespoon | 13.8 g |
| 1/4 cup (4 tbsp) | 55 g |
| 1/3 cup | 73.3 g |
| 1/2 cup (8 tbsp) | 110 g |
| 3/4 cup (12 tbsp) | 165 g |
| 1 cup (16 tbsp) | 220 g |
| 2 cups | 440 g |
| 100 g | 0.45 cups |
There are 3 teaspoons in a tablespoon and 16 tablespoons in a cup, so you can move between any of these measures by multiplying or dividing. If a recipe calls for 100 g and you only have measuring cups, that is about 0.45 cups. Keep the cups to grams converter open while you cook and you will never need to do the arithmetic in your head.
What is Mayonnaise?
Emulsified oil, egg and vinegar spread. Mayonnaise is used for sandwiches, dressings, dips and coleslaw. The ingredient is a familiar one in most kitchens, but it is worth knowing what it actually is before you measure it, because the form it comes in decides how it behaves in a recipe. Mayonnaise as sold is the form the weight on this page refers to: 220 g per cup, spooned and levelled, from USDA. If you buy it in a different form — chopped, ground, toasted, sweetened or unsweetened — the weight per cup changes, sometimes by a lot, so weigh the ingredient in the form the recipe asks for, or weigh it before you change its form. That single habit, weighing before chopping, grinding or toasting, is what keeps the recipe consistent from one bake to the next.
How to measure Mayonnaise
Spoon the mayonnaise lightly into the measuring cup or spoon, then level the top with the back of a knife. Do not scoop the measure straight from the bag or the jar, because scooping packs the ingredient down and adds weight with every spoonful. Do not press it down or shake the measure to settle it, because that packs it too. The spooned and levelled method is a technique, not a machine setting, so two people measuring the same ingredient can still differ by a few grams, which is why the figures on this page are approximate. When the recipe matters, weigh the mayonnaise on a kitchen scale instead: put the bowl on the scale, press tare, and add the mayonnaise until the scale reads the weight you need.
How to store Mayonnaise
Refrigerate after opening; use within 2 months. That storage advice is worth following, because mayonnaise goes stale faster than most cooks expect, and stale mayonnaise will spoil a whole batch of baking. Keep it sealed, because air and moisture are what make it go stale, and keep it away from strong smells, because it absorbs odours from the cupboard. Check the ingredient before you use it: smell it, taste a little, and look at it. If it smells sharp, stale or off, or if it has changed colour or texture, replace it rather than risking a recipe on it. A small amount of fresh mayonnaise is always better than a large amount of stale mayonnaise, and the cost of replacing it is far less than the cost of a ruined bake.
What to use instead of Mayonnaise
If you run out of mayonnaise, the closest swaps are Sour Cream at 230 g per cup, Yogurt at 245 g per cup. Swap by weight, not by volume, because the cup weights differ, and a volume swap gives the wrong amount. Each substitute changes the flavour a little, so choose the one that suits the dish: a mild substitute for a delicate bake, and a stronger one where the flavour can carry it. Taste the finished dish before serving, because a substitute that works in a salad may not work in a cake, and the other way round.
Worked examples: Mayonnaise in real recipes
1. A coleslaw for a barbecue
A coleslaw for eight uses 12 tablespoons of mayonnaise, about 165 g, mixed with a little vinegar and sugar and tossed through shredded cabbage and carrot. The mayonnaise coats the vegetables and gives the slaw its creaminess, and the weight is what decides whether the slaw is creamy or soupy: too much mayonnaise and the slaw turns wet and heavy, too little and it stays dry and crunchy. Start with less than you think you need, toss the slaw well, and add more only if the vegetables look dry.
2. A potato salad for a picnic
A potato salad for six uses 10 tablespoons of mayonnaise, about 137.5 g, folded through warm, sliced potatoes with spring onions and herbs. The mayonnaise coats the potatoes and gives the salad its richness, and the weight matters because too much makes the salad greasy, while too little leaves the potatoes dry. Fold the mayonnaise through the potatoes while they are still warm, so it coats them evenly, and chill the salad before serving so the flavours develop.
3. A sandwich spread for lunchboxes
A sandwich spread for two lunchboxes uses 4 tablespoons of mayonnaise, about 55 g, spread thinly on the bread with a little mustard. The mayonnaise adds richness and stops the bread drying out, and the amount matters: too much makes the sandwich soggy by lunchtime, too little leaves it dry. Spread it thinly and evenly, and keep the sandwich in a sealed box, because mayonnaise dries out in the open air.
Why the weight of Mayonnaise matters
Mayonnaise matters by weight because it is used as a dressing and a binder, and both jobs depend on the ratio. In a coleslaw, the mayonnaise content decides whether the slaw is creamy or soupy, and a 20 g error is enough to tip it: too much mayonnaise and the slaw turns wet and heavy, too little and it stays dry and crunchy. In a sandwich, the mayonnaise adds richness and moisture, and too much makes the bread soggy. The cup measure is unreliable because mayonnaise is thick and clings to the sides of the measure, so a scooped cup can be 15 g heavier than a spooned and levelled one. Weighing it keeps the ratio right, and it also matters because mayonnaise is high in fat and calories, so a recipe that says a cup can hide a wide range of actual amounts if the cook measures by eye.
The USDA figure, and how it was measured
The USDA figure for mayonnaise is not disputed: 220 g per cup, spooned and levelled, is the accepted value, and other sources agree within a few grams. Small differences between brands and batches are normal, because natural ingredients vary, but the variation is small enough that the figure on this page is a reliable guide for everyday cooking. The figure on this page, 220 g per cup, was measured spooned and levelled, which is the standard method for this kind of ingredient. If you measure it differently — scooping instead of spooning, packing instead of levelling, or measuring after chopping — the weight changes, and the recipe changes with it. The source matters too: USDA is the reference used throughout this site, because its figures are consistent and widely used in baking, and the USDA figures are used where King Arthur does not publish one. When two sources disagree, this site says so, and the figure given is the one judged most reliable for everyday cooking.
Common mistakes with Mayonnaise
The most common mistake is adding too much mayonnaise to a coleslaw or a potato salad: the dressing should coat the vegetables, not drown them. Start with less than you think you need, and add more if the salad looks dry. The second mistake is using mayonnaise straight from the fridge in a warm dish, where it can split and turn oily; let it come to room temperature first. The third mistake is storing opened mayonnaise in the cupboard, where it goes off quickly; refrigerate it and use it within two months. Finally, do not use mayonnaise as a direct substitute for yogurt or sour cream in a hot sauce, because it splits when heated, while yogurt and sour cream are more stable.
Frequently asked questions
How many grams is 1 cup of mayonnaise?
One cup of mayonnaise weighs about 220 g, spooned and levelled, using the USDA figure. That is for mayonnaise as sold, and the weight is high because mayonnaise is mostly oil. The figure is approximate, so verify with a kitchen scale when the recipe matters.
How many tablespoons is 100 grams of mayonnaise?
100 grams of mayonnaise is about 7.3 tablespoons, spooned and levelled, because one tablespoon weighs about 13.8 g. Seven level tablespoons is just under 100 g, so add a small spoonful more, or weigh the mayonnaise on a scale, which is easier because it clings to the spoon.
Can I substitute yogurt for mayonnaise?
Yes, in dressings and dips, where the swap is straightforward: 100 g of plain yogurt replaces 100 g of mayonnaise, and the result is lighter and tangier. The texture is different, because yogurt is thinner and less rich, so the dressing may need a little oil to match the creaminess. Do not use yogurt in a hot sauce, because it can split when heated.
How long does mayonnaise keep after opening?
Refrigerate it after opening and use it within 2 months. Opened mayonnaise goes off quickly at room temperature, and even in the fridge it does not last forever. If it smells sharp or looks separated, throw it away, because spoiled mayonnaise can make you ill.
Why does my mayonnaise split when heated?
Because mayonnaise is an emulsion of oil, egg and vinegar, and heat breaks the emulsion, separating the oil from the rest. Mayonnaise is not meant to be heated: use it cold in dressings, dips and sandwiches, and use cream or yogurt for hot sauces, which are more stable when heated.