Peanut Butter: Cups to Grams
A cup of peanut butter is 270 g of dense, clingy, level-it-if-you-can spread — the ingredient that most makes the case for owning a scale.
Peanut butter conversion table
| Cups | Grams | Ounces |
|---|
Stir first — the oil layer breaks every measurement
Natural peanut butter separates in the jar: oil rises, solids sink, and a cup scooped from the top of an unstirred jar is a different ingredient — fattier, thinner — from a cup scooped from the bottom. The King Arthur chart's figure (135 g per half cup, 270 g per cup) describes peanut butter as a single mixed product, so stir the jar thoroughly before measuring anything, working the oil all the way down to the base. Conventional no-stir peanut butters hold their emulsion and measure more consistently, but the chart gives one figure for peanut butter generally, and this page converts both styles at 270 g.
Chunky versus smooth is the other question the chart answers with silence: it lists one peanut butter entry, so one weight. Chunks change how a cup packs at the margins — a knife-levelled cup of chunky holds small air gaps around the pieces — but not enough for any published chart to split the entry, and not enough to adjust a recipe over.
Measuring something that refuses to leave the cup
Fill the cup by pressing the spread in with a spatula in small additions, pushing out air pockets as you go — a cup filled in one big dollop hides a void in the middle and under-measures while looking heroic. Level across the top with a knife, then resign yourself to the scrape-out: a flexible silicone spatula recovers most of it. Most of it is not all of it, which is why the honest method for baking is the scale: set the mixing bowl on it, tare, and spoon peanut butter straight in until the display shows the grams from the converter above. Nothing to scrape, nothing lost, and the cup stays clean in the drawer where it belongs.
Small quantities: a level tablespoon of peanut butter is about 17 g, calculated from the cup figure (270 ÷ 16). "Level" is doing heavy lifting in that sentence — a heaped tablespoon of something this dense can carry half as much again, so for cookies where peanut butter is the recipe, weigh the spoonfuls' total instead.
Frequently asked questions
How many grams is 1 cup of peanut butter?
270 grams per US cup, from the King Arthur chart's 135 g per 1/2 cup doubled. Stir natural peanut butter fully before measuring so the cup matches the mixed product the chart describes.
How many grams is a tablespoon of peanut butter?
About 17 g, calculated from the cup figure (270 g ÷ 16 = 16.9 g). It assumes a level tablespoon — a heaped one of something this dense weighs noticeably more.
Do chunky and smooth peanut butter weigh the same per cup?
The King Arthur chart publishes a single peanut butter figure — 270 g per cup — covering both. Chunks leave tiny air gaps in a levelled cup, but no published chart splits the difference, and neither does this site.
Why is peanut butter heavier than butter per cup?
Density. A cup of butter is 226 g; a cup of peanut butter is 270 g because the spread packs ground peanuts and oil into the volume with very little air, while butter holds more water and air from churning and working.
Related pages
- Butter: cups to grams — 226 g per cup — the spread it's compared against above
- Honey: cups to grams — the other ingredient that won't leave the measuring cup
- Sugar: cups to grams — peanut butter cookies are half sugar by the cup
Data sources: King Arthur Baking Ingredient Weight Chart and USDA FoodData Central. Weights are per US customary cup (236.588 mL); other cup sizes are scaled by volume ratio. See the data sources & method page for how values were chosen.