1/2 Cup Active Dry Yeast in Grams
1/2 cup of active dry yeast weighs 72 g (spooned and levelled, King Arthur Baking). Dormant yeast granules that must be dissolved in warm water before use. All the figures on this page are approximate conversions based on the King Arthur Baking value, so when a recipe really matters, verify with a kitchen scale. Active dry yeast is the ingredient that turns flour and water into bread, and a half cup of it is a bakery amount: the kind used for a morning of loaves, a pile of pizza doughs or a dough being scaled up for a market stall.
Why half a cup of active dry yeast is a useful amount
Half a cup of active dry yeast 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 active dry yeast leaves a soapy, metallic taste and a collapsed crumb, while a few grams too little leaves a dense, flat bake. Breads, pizza dough, rolls and brioche. The table below is built from the published King Arthur Baking weight, so you can convert a bulk recipe to grams once and trust the number every time you repeat it.
Active Dry Yeast 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 active dry yeast 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 King Arthur Baking, and the confidence in the value is medium. King Arthur Baking 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.
King Arthur lists instant yeast at 144 g per cup; active dry yeast is sold in 7 g packets and has a similar density. We use 144 g with medium confidence.
Worked examples
A morning of loaves for a bakery
A small bakery starting the morning with thirty loaves uses 1/2 cup of active dry yeast, which is 72 g, bloomed in warm water before it meets the flour. The yeast has to be alive and evenly distributed, or some loaves rise on schedule while others lag behind. Weighing 72 g keeps the ferment consistent, and the water must be warm, not hot: water above 50 C kills the yeast outright.
A pizza dough batch for a party
A pizza night for twenty people needs dough for ten bases, and the recipe scales the active dry yeast to 1/2 cup, which is 72 g. The dough is mixed in the morning and left to rise slowly, so the yeast amount decides whether the bases are ready by evening or still sluggish. Weighing 72 g gives a predictable rise, and the dough can be chilled overnight to slow it down.
Doubling a brioche for a celebration
A brioche doubled for a celebration scales the yeast to 1/2 cup, which is 72 g, folded into an enriched dough full of butter and eggs. Enriched doughs rise slowly because the fat and sugar weigh the yeast down, so the weighed amount matters even more than in a lean dough. Weighing 72 g and giving the dough a long, cool rise keeps the crumb light.
When this conversion matters most
This conversion matters most when you are scaling a recipe that depends on chemistry. A teaspoon of active dry yeast 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 active dry yeast
- 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
Cool, dry place; refrigerate after opening and check the expiry date. Keeping active dry yeast 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 active dry yeast?
1/2 cup of active dry yeast weighs 72 g, measured spooned and levelled according to King Arthur Baking. 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 active dry yeast 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 active dry yeast 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 King Arthur Baking value for active dry yeast 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 active dry yeast?
Yes, as a starting point. The 144 g figure is a standard average for active dry yeast, 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.
Is active dry yeast the same weight as instant yeast?
Not exactly, and this page carries the note because it matters. King Arthur lists instant yeast at 144 g per cup, while active dry yeast is usually quoted slightly differently because the granules are larger and pack less tightly, so the two are not interchangeable by the cup. A half cup of active dry yeast is 72 g by the value on this page. If your recipe was written for instant yeast, use a yeast converter to swap the type rather than weighing the same grams.
How should I store active dry yeast?
Cool, dry place; refrigerate after opening and check the expiry date. 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.