45 Grams of Peanut Butter in Cups
45 grams of peanut butter doesn't land on a clean fraction, so the result below is calculated exactly rather than rounded to a common measure. Based on a density of 258g per cup, it equals 0.17 cups.
- Cups (US Customary)
- 0.17 (⅛)
- Tablespoons
- 2.8
- Teaspoons
- 8.4
- Milliliters
- 41 ml
45 grams of peanut butter = 0.17 cups (⅛ cup / 2.8 tbsp / 8.4 tsp)
Peanut Butter has a density of approximately 258g per cup. Creamy, natural style runs closer to 240g. Source: USDA FoodData Central. This is the figure used everywhere on this page, including the tablespoon and teaspoon values, so the numbers stay consistent whether you're reading the summary line, the table, or the FAQ answers below.
| Grams | Cups | Fraction | Tablespoons | Teaspoons |
|---|---|---|---|---|
| 35g | 0.14 | ⅛ | 2.2 | 6.5 |
| 40g | 0.16 | ⅛ | 2.5 | 7.4 |
| 45g | 0.17 | ⅛ | 2.8 | 8.4 |
| 50g | 0.19 | ¼ | 3.1 | 9.3 |
| 55g | 0.21 | ¼ | 3.4 | 10.2 |
How 45g Converts, Step by Step
45g divided by 258g (the weight of one cup of peanut butter) equals 0.17 cups. Multiplying that by 16 gives 2.8 tablespoons, and by 48 gives 8.4 teaspoons, since one cup always equals 16 tablespoons or 48 teaspoons regardless of the ingredient.
Peanut Butter is denser than water, which weighs about 236g per cup. That's why 45g of peanut butter fills less volume (41ml) than the same weight of water would (45ml). For a side-by-side look at how other ingredients compare, see the 45 grams to cups page.
If You're Using a Metric or Imperial Cup
The 0.17 cup figure above uses the US Customary cup (236.588ml). Recipes written outside the US sometimes use a metric cup (250ml) or an imperial (uk) cup (284.131ml) instead. At 45g, that's ⅛ metric cups or ⅛ imperial cups of peanut butter, close to the US figure but not identical. The cup standard switch in the converter above recalculates this instantly for any gram amount.
Scaling This 45g Amount
Doubling a recipe that calls for 45g of peanut butter means weighing 90g, or measuring 0.35 cups if you're working by volume instead of weight. Halving it means 22.5g, or 0.09 cups. Weight scales exactly with simple multiplication; cup measurements compound any scooping error each time they're doubled or halved, so weighing is more reliable the more a recipe is scaled.
Peanut Butter Next to Other Condiments & Sauces
Within condiments & sauces, density still varies by ingredient. At 45g, almond butter (240g per cup) measures ⅛ cup, while tahini (240g per cup) measures ⅛ cup, compared to ⅛ cup for peanut butter. Swapping ingredients in a recipe by cup measurement alone, without adjusting for this difference, changes the actual weight used.
Where This Amount Shows Up in Recipes
- Peanut butter cookies typically use 130g to 260g per batch.
- Smoothies often call for 30g (about 2 tablespoons) per serving.
- No-bake energy bites usually need about 130g for a dozen.
Measuring This Precisely
Condiments & Sauces
Use a spatula to level thick condiments like peanut butter or tahini after pressing them into the cup to remove air gaps.
For exact results
Stir thick condiments well before measuring, since separation during storage (common in natural nut butters) can make the top and bottom of the jar measure differently.
For every gram amount at once, the peanut butter conversion chart lists peanut butter across the full range from 1g to 1000g in one table.
Frequently Asked Questions
What is 45 grams of peanut butter in cups exactly?+
45 grams of peanut butter equals 0.17 cups, based on a density of 258g per cup.
Why doesn't 45g of peanut butter match a simple fraction?+
45g isn't a multiple of peanut butter's per-cup weight, so the cup value lands between common fractions. The closest practical measure is ⅛ cup.
What's the most reliable way to measure 45g of peanut butter?+
A kitchen scale set to grams gives an exact 45g reading. Cups only approximate this amount, since ⅛ cup rounds to the nearest practical fraction.
Is 45g likely a typo for a rounder amount?+
Possibly, if a recipe seems to expect a cleaner number. Check the nearby amounts table below for the closest common gram values for peanut butter.