1/2 Cup Cream of Tartar in Grams
1/2 cup of cream of tartar weighs 72 g (spooned and levelled, USDA). Acidic white powder left over from winemaking. All the figures on this page are approximate conversions based on the USDA value, so when a recipe really matters, verify with a kitchen scale. Cream of tartar is the quiet stabiliser of the baking world: it steadies egg whites, keeps sugar syrups from crystallising and gives baking powder its acid, and a half cup of it belongs in a meringue for a crowd or a bakery batch of snickerdoodles.
Why half a cup of cream of tartar is a useful amount
Half a cup of cream of tartar is an industrial amount: no home recipe asks for it, which is exactly why the conversion matters. Leaveners are chemistry in small doses, and the recipes that do use a half cup are bulk bakes, bakery batches and recipes being scaled up from a single cake to a dozen. At that scale a cup measure is far too coarse: a few grams too much cream of tartar leaves a soapy, metallic taste and a collapsed crumb, while a few grams too little leaves a dense, flat bake. Stabilising egg whites, activating baking soda and making baking powder. The table below is built from the published USDA weight, so you can convert a bulk recipe to grams once and trust the number every time you repeat it.
Cream of Tartar cups to grams conversion table
| Cups | Grams | Tablespoons (approx.) |
|---|---|---|
| 1/4 cup | 36 g | 2.2 g |
| 1/3 cup | 48 g | 3 g |
| 1/2 cup | 72 g | 4.5 g |
| 2/3 cup | 96 g | 6 g |
| 3/4 cup | 108 g | 6.8 g |
| 1 cup | 144 g | 9 g |
| 1 1/2 cups | 216 g | 13.5 g |
| 2 cups | 288 g | 18 g |
| 3 cups | 432 g | 27 g |
| 4 cups | 576 g | 36 g |
The tablespoon column is a bonus for recipes that call for a spoonful or two: one tablespoon of cream of tartar weighs about 9 g, and one teaspoon about 3 g. A cup is 16 tablespoons, so the numbers in the table are just the cup weight divided by 16, rounded to one decimal place. For small amounts a scale that reads to the gram is far more reliable than a spoon, because a heaped tablespoon can weigh half as much again as a level one.
How the weight was measured
Spooned and levelled means spooning the ingredient into the measuring cup until it is heaped, then sweeping a straight knife across the top to level it off. Never scoop the cup through the bag or jar, and never tap the cup down, because both pack the ingredient and add weight.
The source for the 144 g figure is USDA, and the confidence in the value is medium. USDA publishes a standard ingredient weight chart that recipe developers use as a reference, and this page follows it exactly rather than averaging across sources, because an average of two different measuring methods is a number that matches nobody's cup.
Worked examples
A meringue for a wedding cake
A meringue for a wedding cake uses 1/2 cup of cream of tartar, which is 72 g, beaten into a dozen egg whites. The cream of tartar stabilises the foam so it holds its shape through piping and baking, and without it the meringue weeps. Weighing 72 g keeps the foam firm, and the bowl must be scrupulously clean: a trace of fat collapses egg whites faster than any missing ingredient.
A bulk batch of snickerdoodles
A bakery batch of snickerdoodles calls for 1/2 cup of cream of tartar, which is 72 g, sifted into the flour. The cream of tartar gives the cookies their tang and their chew, and it is the ingredient that makes a snickerdoodle taste like a snickerdoodle rather than a sugar cookie. Weighing 72 g keeps the tang consistent across the whole batch.
A sugar syrup for a large batch of sweets
A sugar syrup for a large batch of sweets uses 1/2 cup of cream of tartar, which is 72 g, stirred in to stop the syrup crystallising. The acid inverts some of the sugar, which keeps the syrup smooth and glossy as it cools. Weighing 72 g keeps the syrup clear, and the pan must not be stirred once it boils, or crystals form regardless.
When this conversion matters most
This conversion matters most when you are scaling a recipe that depends on chemistry. A teaspoon of cream of tartar is easy to measure, but a half cup is a large amount of a powerful ingredient, and the difference between a level half cup and a heaped one can be more than ten grams. In a cake that difference decides whether the crumb rises evenly or tunnels and collapses; in a dough it decides whether the rise happens on schedule or runs away while you are still shaping. Weighing is the only reliable way to scale leavening up or down, and it is also the only way to repeat a bake that worked.
Common mistakes with cream of tartar
- Measuring leaveners by the cup. Leaveners are powerful in tiny amounts, and a cup measure is far too coarse for them. A heaped half cup can hold far more than the recipe intended. Weigh them, even when the recipe gives cups.
- Scooping straight from the tin. Scooping packs the powder down and adds weight. Spoon it into the cup and level it, or better, put the bowl on the scale and weigh it directly.
- Scaling leavening linearly. Doubling a recipe does not always mean doubling the leavener: a doubled cake often needs slightly less than double. Weigh the amount, then check the ratio against a tested recipe.
- Using an old, damp tin. Leaveners absorb moisture and lose strength as they age, which changes both their weight per cup and their power. Keep the tin sealed and dry, and test old stock before a big bake.
Storage and handling
Airtight jar, cool and dry, up to 3 years. Keeping cream of tartar stored properly also keeps its weight per cup stable: an ingredient that has absorbed moisture from the air weighs more per cup than a dry one, so a sealed container is not just about freshness, it is about measurement accuracy too. If a bag has been open for months in a humid kitchen, the first thing to do before a precise bake is to weigh the ingredient rather than trusting the cup.
Frequently asked questions
How many grams is 1/2 cup of cream of tartar?
1/2 cup of cream of tartar weighs 72 g, measured spooned and levelled according to USDA. That is the figure to use when converting a recipe from cups to grams, and it is the value the conversion table on this page is built on.
How do I measure cream of tartar without a scale?
Spooned and levelled means spooning the ingredient into the measuring cup until it is heaped, then sweeping a straight knife across the top to level it off. Never scoop the cup through the bag or jar, and never tap the cup down, because both pack the ingredient and add weight. That gives the closest result to 72 g per half cup, but it is still an estimate: the honest answer is that a scale is the only way to know the exact weight, and a basic digital kitchen scale costs less than a bag of good flour.
Does cream of tartar always weigh the same per cup?
No. Brand, grind, moisture and how settled the container is all shift the weight by a few grams, and for some ingredients the swing can be much larger. The 144 g figure is the standard USDA value for cream of tartar measured spooned and levelled, and it is the right default, but when a recipe is precise, weigh the ingredient and trust the scale over the cup.
Can I use the same conversion for a different brand of cream of tartar?
Yes, as a starting point. The 144 g figure is a standard average for cream of tartar, and most brands sit within a few grams of it. If you cook with one brand all the time, weigh one cup of it once and note the number on the bag, and you will have a conversion tuned to your own kitchen.
What does cream of tartar actually do in baking?
Three things: it stabilises whipped egg whites so meringues hold their shape, it supplies the acid that activates baking soda in recipes without buttermilk, and it stops sugar syrups from crystallising. A half cup is 72 g, which is a bulk amount, and at that scale the acid matters: too much cream of tartar makes a bake taste sharp, while too little leaves a meringue that weeps. Weigh it, and keep the tin sealed, because it absorbs moisture from the air.
How should I store cream of tartar?
Airtight jar, cool and dry, up to 3 years. Good storage keeps the ingredient fresh and keeps its weight per cup consistent, because moisture absorbed from the air adds grams that the recipe did not ask for.
Related conversions
Use the cups to grams converter, tablespoons to grams converter, weight converter, baking powder to soda converter for instant answers, or browse the cups to grams hub for the full ingredient list. Related pages: Baking Soda in cups to grams, Baking Powder in cups to grams, Salt in cups to grams. See also our disclaimer about approximate conversions.