A 12 oz bag of sunflower seeds holds about 2.4 cups. Shelled sunflower seeds weigh about 140 g per cup, so 340 g divides to 2.4 cups — enough for several trays of granola, a few loaves of bread and a month of salads. The 12 oz bag is the standard size for shelled seeds, and the figure is for shelled seeds only: a bag of seeds in the shell yields far less edible weight.
How many cups in a 12 oz bag?
A 12 oz bag of sunflower seeds holds about 2.4 cups (340 g ÷ 140 g per cup).
| Amount | Cups | Grams | Tablespoons |
|---|---|---|---|
| Full 12 oz bag | 2.4 | 340 | 38 |
| Half 12 oz bag | 1.2 | 170 | 19 |
| Quarter 12 oz bag | 0.6 | 85 | 10 |
| 1 tablespoon | 0.06 | 8.75 | 1 |
The table gives the full package, half a package and a quarter of a package, plus a single tablespoon, so you can scale the answer to whatever your recipe asks for. If your packet is a different size from the one on this page, the same per-cup figure still applies — divide your packet's weight by the grams per cup, or its volume by 236.6 ml per cup, and you have your answer.
Worked examples
Granola that needs a cup
A tray of granola takes about 1 cup of sunflower seeds — 140 g — tossed with 3 cups of oats, 1/2 cup of nuts and 1/3 cup of honey. One cup is just under half the bag, so a 12 oz bag makes about two and a half trays. Add the seeds with the oats rather than at the end: they toast along with the oats and develop a nutty flavour, while seeds added late taste raw and soft. Stir the granola halfway through baking so the seeds toast evenly.
Seeded bread that needs half a cup
A loaf of seeded bread takes about 1/2 cup of sunflower seeds — 70 g — mixed into a dough with 3 cups of flour, 1 and a half cups of water and 2 teaspoons of yeast, plus a few more scattered on top. Half a cup is about a fifth of the bag, so one bag covers about five loaves. Soak the seeds for twenty minutes before adding them to the dough: dry seeds absorb water from the dough and make the crumb dry, while soaked seeds stay plump.
Salad topping that needs a quarter of a cup
A large salad for six takes about 1/4 cup of sunflower seeds — 35 g — toasted and scattered over the top. A quarter of a cup is about a tenth of the bag, so one bag tops about ten salads. Toast the seeds in a dry pan for two minutes until they smell nutty: raw sunflower seeds taste flat, while toasted ones are sweet and rich. Let them cool before scattering or they wilt the leaves.
How the figure was measured
The weight figure on this page comes from King Arthur Baking: sunflower seeds weighs 140 g per cup, measured spooned and levelled, and that figure carries high confidence in CookScale's 120-ingredient table. Every cup-based result on this page is approximate, because a cup measures volume and the weight depends on how the ingredient settles, how it was measured, and how fresh it is. When the amount matters — a cake, a cheesecake, a sauce that must set — weigh the ingredient on a kitchen scale instead of trusting the cup. Package sizes vary by brand and region, so check the weight printed on your own packet before planning a recipe around this page.
How to measure it
Nuts are spooned into a dry cup measure and levelled, never packed — pressing them down crushes the pieces and fits far more weight into the same cup. Whole nuts, halves and chopped pieces all measure differently in the same cup: a cup of whole almonds weighs more than a cup of chopped almonds, because the pieces settle differently and the air gaps change. That is why the weight figures on this page are the anchor, not the cup. If a recipe says '1 cup chopped walnuts', chop first and then measure; if it says '1 cup walnuts, chopped', measure first and then chop. The difference is real — about a quarter of a cup in a batch of brownies. When it matters, weigh: 142 g of almonds is 142 g however you chop them.
Practical guidance
Nuts go rancid faster than almost anything else in the pantry because their oils are exposed to air. A bag opened in January and still sitting in a warm cupboard in June will taste stale and a little bitter, and no recipe can hide it. Store opened nuts in a sealed jar in the fridge, or in the freezer for months — they thaw in minutes and toast straight from frozen. Taste one before baking with an old bag: fresh nuts taste sweet and clean, stale ones taste like old oil. Toasting revives nuts that are merely flat, but it cannot rescue ones that have turned. Buy smaller bags more often rather than one huge bag that sits open.
Two and a half cups is the working figure, and the shelled-versus-in-shell distinction is the trap: a bag of seeds in the shell looks identical on the shelf but yields a third of the edible seeds. Check the label for 'shelled' or 'kernels' before you buy. The bag size varies too — 8 oz bags hold about 1.6 cups and 16 oz bags about 3.2 cups — and the same 140 g per cup applies to shelled seeds throughout. And store them in the fridge once opened: sunflower seeds go rancid faster than most pantry staples, and a bag left in a warm cupboard for months will not taste like the seeds the recipe was written with.
Frequently asked questions
How many tablespoons are in a 12 oz bag of sunflower seeds?
There are about 38 tablespoons in a 12 oz bag of sunflower seeds, because the bag holds about 2.4 cups and there are 16 tablespoons in a cup. A tablespoon of shelled sunflower seeds weighs about 8.8 g. For a salad topping, 1 to 2 tablespoons per serving is the usual amount, so a bag covers roughly two dozen servings.
Are sunflower seeds in the shell the same as shelled seeds?
No. The figure on this page, 140 g per cup, is for shelled sunflower seeds only. Seeds in the shell are mostly shell by volume, and a cup of in-shell seeds yields far less edible weight — roughly a third. For cooking and baking, always buy shelled seeds; in-shell seeds are a snack, not an ingredient.
Can I substitute sunflower seeds for pumpkin seeds?
Roughly, by volume, but the weights differ: sunflower seeds weigh about 140 g per cup, while pumpkin seeds are heavier at about 150 g per cup. In a granola or a bread the difference is small, but in a recipe that depends on the seed for structure, weigh the substitute. Flavour-wise they are close — both are mild and nutty — and the swap works well in most recipes.
How long does an opened bag of sunflower seeds last?
An opened bag of sunflower seeds lasts about three months in a cool cupboard and six months in the fridge. Store them in a sealed jar, not the open bag. Sunflower seeds are high in unsaturated oils and go rancid faster than most seeds, so taste a few before baking with an old bag — fresh seeds taste sweet and nutty, stale ones taste bitter and oily.
Should I toast sunflower seeds before measuring them?
Measure first, then toast. Toasting shrinks the seeds slightly and changes their weight, so a cup measured after toasting is not the same as a cup measured before. If a recipe says '1 cup toasted sunflower seeds', measure a cup of raw seeds and then toast them in a dry pan for two to three minutes, shaking the pan so they toast evenly.