Protein head-to-heads · July 2026
Oats (dry) vs Peanut butter: which protein is cheaper?
USDA macros joined to current US grocery prices, reduced to the two numbers that decide it: dollars per gram of protein, and protein per calorie.
Oats (dry) is 2.5x cheaper per gram of protein ($0.009/g vs $0.022/g), while it also carries more protein per calorie (4.3 g vs 4.3 g per 100 kcal), so it wins on both axes.
| Food | $/g protein | 30 g protein costs | You need | kcal that come with it | Protein/100 kcal |
|---|---|---|---|---|---|
| Oats (dry) | $0.009 | $0.27 | 178 g | 691 kcal | 4.3 g |
| Peanut butter | $0.022 | $0.66 | 120 g | 706 kcal | 4.3 g |
Full macros, per serving
| Food (per serving) | Price | kcal | Protein | Carbs | Fat |
|---|---|---|---|---|---|
| Oats (dry) (100 g) | $0.15 | 389 | 16.9 g | 66 g | 6.9 g |
| Peanut butter (100 g) | $0.55 | 588 | 25 g | 20 g | 50 g |
A week of protein from each
Hitting a common 100 g/day protein target from oats (dry) alone costs $6.21 a week; from peanut butter alone, $15.40. That is a gap of $9.19 every week for the same protein. In practice you mix sources: the planner computes the cheapest mix for your exact target and calorie cap, live from the same dataset.
This one is not a trade-off
Oats (dry) is both the cheaper protein ($0.009/g against $0.022/g) and the leaner one (4.3 g protein per 100 kcal against 4.3 g). Most matchups force you to pick a side. This one does not, so peanut butter has to win on taste, prep time or what else it brings to the meal, because it is not winning on the numbers.
What the calories cost you
Getting 30 g of protein from peanut butter brings 706 kcal with it. On a 2,000 kcal day, three servings would be most of your budget before anything else goes on the plate. That is fine when you are eating at maintenance or building, and it is the reason this food falls apart on a cut no matter how good the price per gram looks.
Two budget staples, so the tiebreak is elsewhere
Both of these sit in the cheapest third of everything we track (#1 and #7 of 25), and the difference between them is $0.39 per 30 g of protein. That is small enough that shelf life, prep time and whether you will actually eat it should decide this, not the price column.
Compare against other foods
- Oats (dry) vs Lentils (cooked)Peanut butter vs Lentils (cooked)
- Oats (dry) vs Tofu (firm)Peanut butter vs Tofu (firm)
- Oats (dry) vs Black beans (cooked)Peanut butter vs Black beans (cooked)
- Oats (dry) vs Whey protein (1 scoop)Peanut butter vs Whey protein (1 scoop)
- Oats (dry) vs Greek yogurt (nonfat)Peanut butter vs Greek yogurt (nonfat)
- Oats (dry) vs Eggs (~2 large)Peanut butter vs Eggs (~2 large)
- Oats (dry) vs Chicken breast (raw)Peanut butter vs Chicken breast (raw)
- Oats (dry) vs Canned tuna (in water)Peanut butter vs Canned tuna (in water)
Frequently asked
- Which is cheaper for protein, oats (dry) or peanut butter?
- Oats (dry), at $0.009 per gram of protein against $0.022 for peanut butter (July 2026 US grocery prices). A 30 g protein serving costs $0.27 vs $0.66.
- Which has more protein per calorie, oats (dry) or peanut butter?
- Oats (dry), with 4.3 g protein per 100 kcal against 4.3 g for peanut butter, 1.0x leaner. That matters when you are cutting and calories are the binding constraint.
- Which should I buy, oats (dry) or peanut butter?
- Oats (dry) wins on both axes here: cheaper per gram of protein and more protein per calorie. Unless taste, prep or the rest of your macros say otherwise, it is the better default.
Prices are representative US grocery prices as of July 2026; your store will differ. Educational content, not medical or dietary advice. Dataset: free download, CC-BY.