Does spirulina or whey protein isolate have more protein?
Whey protein isolate, at 90g per 100g versus 57g for spirulina.
Spirulina vs Whey protein isolate: Which Has More Protein?
Whey protein isolate wins on protein: 90g per 100g versus 57g, a gap of 33g. Calories and protein quality change the picture, so here is the full comparison.
Head to head, per 100g
| Food | Protein | Calories |
|---|---|---|
| 🥤 Whey protein isolate | 90g | 400 |
| 🌿 Spirulina (dried) | 57g | 290 |
Per 100g.
What the numbers mean
Spirulina delivers 57g of protein for 290 calories per 100g. Whey protein isolate delivers 90g for 400 calories. If you are counting calories as well as protein, spirulina is the leaner choice per 100g.
Protein quality: spirulina is a complete protein, whey protein isolate is a complete protein. Complete proteins carry all nine essential amino acids in useful amounts; incomplete ones are still valuable, they just want a complementary source across the day.
Up to 70% protein by weight — but tiny servings. Fast-absorbing, top DIAAS score. ~27g per scoop.
Which should you choose?
- For maximum protein per 100g: whey protein isolate (90g).
- For the fewest calories per 100g: spirulina.
- For everyday practicality, the better choice is the one you will actually eat regularly — the difference between 57g and 90g matters far less than consistency across the week.
- Mixing both across the week covers a wider spread of micronutrients than committing to one.
Add up your whole meal
Type what you ate in plain words and Protein Hunter returns protein and calories for the full plate.
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Which has fewer calories, spirulina or whey protein isolate?
Spirulina — 290 calories per 100g versus 400.
Can I swap one for the other in a recipe?
Usually yes, but adjust the weight so the protein matches. To replace 100g of whey protein isolate you need about 158g of spirulina.
Keep reading
Protein in spirulina57g per 100g in full detail.Protein in whey protein isolate90g per 100g in full detail.Compare any two foodsSearch the full protein database.What is Protein Hunter?
Protein Hunter is a protein and nutrition app with a database of 232 foods — from a leaf of kale to a wagyu steak — plus AI tools that answer protein questions, count a whole meal, build recipes to a macro target, and track what you actually eat.
- Search any food
- Count a full meal
- Recipes to your macros
- Scan a plate or label
Why it's different: the numbers are calculated from a fixed ingredient database rather than guessed, and when a target is not physically achievable the app says so instead of inventing a figure.
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