If a recipe calls for a cup of jam and your measuring jug is marked in millilitres, the answer you need is simple — but only half of it is simple. The volume is fixed: 1 US cup is 236.6 ml, whatever you put in it. The weight is not fixed at all, and that is where most kitchen mistakes happen. One cup of jam weighs about 320 g, measured spooned and levelled according to USDA, and that single number is the key to converting the recipe accurately, scaling it up or down, and knowing whether the amount in your bowl is actually the amount the recipe intended. This page gives you both numbers, the full cups-to-millilitres table, worked examples from real recipes, and the measuring method behind the figures, so you can stop guessing and start weighing.
How much is 1 cup of jam in millilitres?
1 cup of jam is 236.6 ml and weighs about 320 g. The millilitre figure is exact, because a US cup is defined as 236.6 ml: fill any cup measure to the brim with any ingredient and you have 236.6 ml of it. The gram figure is approximate, because it depends on the density of jam and on how the cup was filled. The value we use, 320 g, comes from USDA, measured spooned and levelled, and we use it with medium confidence. If you are baking, scaling a recipe, or cooking for someone with a dietary restriction, weigh the jam on a kitchen scale and use the gram figure — it is the only measurement that does not depend on how fluffy, damp or tightly packed the ingredient happens to be today.
That distinction between exact volume and approximate weight is the single most useful thing to understand about cup conversions. Recipes written in cups assume a standard cup and a standard technique, and when either of those assumptions breaks, the recipe breaks with it. A cup of jam scooped straight from the bag can weigh noticeably more than a cup spooned in gently, and the difference is invisible until the finished dish tells you about it. The table below gives you both figures for every amount you are likely to need, so you can convert in either direction without doing the arithmetic yourself.
Cups to millilitres table for jam
| Cups | Millilitres | Grams (approx.) |
|---|---|---|
| ¼ cup | 59.2 ml | 80 g |
| ⅓ cup | 78.9 ml | 107 g |
| ½ cup | 118.3 ml | 160 g |
| ⅔ cup | 157.7 ml | 213 g |
| ¾ cup | 177.5 ml | 240 g |
| 1 cup | 236.6 ml | 320 g |
| 2 cups | 473.2 ml | 640 g |
| 3 cups | 709.8 ml | 960 g |
| 4 cups | 946.4 ml | 1280 g |
Every row in this table follows the same two rules. The millilitre column is the cup fraction multiplied by 236.6 ml, so a quarter cup is 59.2 ml, a third of a cup is 78.9 ml, half a cup is 118.3 ml, two-thirds is 157.7 ml, and three-quarters is 177.5 ml. Those numbers are exact to one decimal place and they are the same for every ingredient on this site. The gram column is the same fraction multiplied by 320 g, the weight of a full cup of jam, and those numbers are approximate: a quarter cup is about 80 g, half a cup about 160 g, and four cups about 1280 g. Use the millilitres when you are measuring volume, and the grams when you are measuring weight — and remember that only the grams need a scale to check.
There is one more conversion worth knowing. One US cup is 8 US fluid ounces, so 1 cup of jam is also 8 fl oz by volume — but fluid ounces are a volume measure, not a weight measure, and jam does not weigh 8 ounces. Do not confuse the two: 8 fl oz of jam is a volume of 236.6 ml, while the weight is about 320 g. If a recipe gives ounces and you are not sure which kind it means, check whether it is talking about a measuring jug (fluid ounces, volume) or a scale (ounces, weight). When a recipe is ambiguous, the gram figure on this page is the safer one to follow.
Worked examples
A marinade that needs half a cup
A marinade that calls for ½ cup of jam needs 118.3 ml, about 160 g. For a thin sauce, measure in a liquid jug at eye level; for a thick paste, weigh it. A marinade is forgiving, but the ratio of sauce to oil and acid is what makes it work, so measure the jam properly and taste the marinade before the meat goes in.
A batch of soup that needs two cups
A soup that uses 2 cups of jam needs 473.2 ml, about 640 g. Add it gradually rather than all at once, tasting as you go — two cups is a lot of flavour, and it is easier to add more than to dilute a soup that is already too rich. If you overshoot, add stock or water a ladle at a time.
Scaling a sauce recipe for the freezer
A sauce you are batch-cooking for the freezer might use 3 cups of jam — 709.8 ml, about 960 g. Weigh or measure the full amount before you start cooking, so you are not interrupting a simmering pot to measure more. Cool the finished sauce quickly, portion it into containers, and label each with the date.
How to measure 1 cup of jam
Jam is a spoon-and-pour ingredient, and the cup figure on this page exists mainly for scaling: home recipes rarely use a whole cup, but a batch of sauce, a marinade for a crowd, or a recipe doubled for a freezer session can easily call for two or three cups. The figure, 320 g per cup, is for jam measured as described below, and because jam is a liquid or a thick paste rather than a dry powder, the method matters less than it does for flour — but it still matters. A thick paste traps air bubbles if you spoon it in carelessly, and a thin sauce clings to the sides of the cup, so the amount that actually lands in the pan can be less than the amount you measured. The practical fix is simple: measure thick pastes by weight when the recipe is fussy, and for thin sauces use a liquid measuring jug and read it at eye level.
The method behind our figure is spooned and levelled, and the source is USDA. In practice that means: take a dry measuring cup, spoon the jam in until it heaps above the rim, then sweep a straight edge — the back of a knife is ideal — across the top to level it. Do not scoop the cup through the ingredient, do not tap the cup on the bench to settle the contents, and do not press the ingredient down. Each of those shortcuts packs more into the cup and makes the weight higher than the 320 g in the table, sometimes by a surprising amount. For a liquid or a pourable ingredient the method is simpler: pour into a liquid measuring jug, set it on a flat surface, and read the level at eye height.
If you do not have a scale, the spooned-and-levelled cup is the best you can do, and for most everyday cooking it is good enough. But if the recipe is a bake, a preserve, or anything where the ratio of ingredients does the structural work, borrow or buy a scale: even a basic digital scale is more accurate than the best cup technique, and it is faster once you are used to it. Put the bowl on the scale, press tare, and add jam until the display reads the grams you need. That is the whole technique, and it removes the single biggest source of variation in cup-based recipes.
Working with jam in real recipes
Jam is used for toast, baking, glazes and thumbprint cookies. Fruit preserves set with sugar and pectin.
Measure thick pastes by weight
Refrigerate after opening; use within 3 months. A thick paste is the hardest thing in the kitchen to measure by volume: it traps air, clings to the spoon, and leaves a film in the cup. If the recipe is a sauce you will taste and adjust, the cup is fine. If it is a recipe where the paste is a structural ingredient — a glaze, a marinade ratio, a batch of soup base — weigh it. The 320 g per cup figure is your bridge between the two.
Thin sauces belong in a jug
For a thin, pourable sauce, use a liquid measuring jug rather than a dry cup: set it on the bench, pour to the millilitre mark, and read it at eye level. A dry cup read from above will always look fuller than it is, and with a strongly flavoured sauce a small over-pour is a big flavour change.
Common mistakes with cups and millilitres
The most common mistake is treating the millilitre figure and the gram figure as interchangeable. They are not: 236.6 ml is a volume and 320 g is a weight, and the only ingredient for which they are equal is water, where 1 ml weighs 1 g. For jam, 236.6 ml weighs about 320 g, and if you weigh out 236.6 g of jam instead of measuring 236.6 ml, you will have the wrong amount — too much if 320 is greater than 236.6, too little if it is less. Always check whether the recipe wants a volume or a weight, and use the matching column of the table.
The second most common mistake is using the wrong cup. A US cup is 236.6 ml, a metric cup is 250 ml, and a UK cup in older recipes can mean something else again. If your measuring cup came with a set that does not say which standard it follows, check it against a measuring jug: fill the cup with water and pour it into the jug. If it reads 236.6 ml, it is a US cup; if it reads 250 ml, it is a metric cup. Once you know, write it on the cup with a permanent marker so you never have to guess again.
The third mistake is measuring over the mixing bowl. It feels efficient, but a spill goes straight into the batter and cannot be taken back, and a cup read from above always looks fuller than it is. Measure over the sink or a plate, level the cup, and then tip it into the bowl. It takes five seconds longer and it prevents the kind of error that ruins a bake.
Frequently asked questions
How many millilitres is 1 cup of jam?
1 cup of jam is 236.6 ml. That figure is fixed: a US cup is defined as 236.6 ml, so it is the same for every ingredient. What changes from one ingredient to another is the weight, and 1 cup of jam weighs about 320 g. The volume never changes; the weight always depends on the ingredient.
How many grams is 1 cup of jam?
1 cup of jam weighs about 320 g, measured spooned and levelled according to USDA. The word "about" matters: the exact weight of a cup depends on how the ingredient is handled, how finely it is ground or cut, and how much moisture it holds. For baking and for any recipe where the amount is critical, weigh the ingredient on a kitchen scale rather than trusting the cup.
Is 1 cup of jam the same as 250 ml?
No. A US cup is 236.6 ml, while a metric cup — used in Australia and in many metric recipes — is 250 ml. The difference is 13.4 ml per cup, which is about 5.7%. If your recipe was written with metric cups and you measure with a US cup, you will be short on every cup; if it was written with US cups and you use a metric cup, you will be over. Check which cup your recipe means, and when in doubt use the gram figure, 320 g, which does not depend on the cup at all.
How many tablespoons of jam are in a cup?
There are 16 tablespoons in 1 cup, so 1 cup of jam is 16 tablespoons, weighing about 320 g in total. One tablespoon is about 20.0 g and one teaspoon is about 6.7 g. These spoon figures are worked back from the cup weight, so they carry the same approximation — they are useful for small amounts, but for a full cup the scale is still the more accurate tool.
How do I measure a thick jam accurately?
Weigh it. Thick pastes trap air and cling to the cup, so a cup measured by volume can be noticeably short of the 320 g it should hold. Put the bowl on the scale, tare it, and spoon the paste in until the display reads the grams you need. For thin, pourable sauces a liquid measuring jug read at eye level is accurate enough.
Can I use a kitchen scale instead of a cup for jam?
Yes, and for most recipes you should. Put your bowl on the scale, press tare to zero it, and add jam until the display reads the grams you need — 320 g for a full cup, 160 g for half a cup, 80 g for a quarter cup. A scale removes every variable that makes cup measuring unreliable: how firmly the ingredient was packed, how it was scooped, and how humid the day is.
Why does the weight of a cup of jam vary between sources?
Different sources measure differently. Some scoop the cup through the ingredient, some spoon it in, some pack it down, and some use a different variety or a different moisture level. The figure on this page, 320 g, comes from USDA using the spooned and levelled method, which is the most repeatable way to fill a cup. If another source gives a different number, it is usually because the method was different — not because one of them is wrong.