Protein Per Calorie Leaders Protein Powders (2026)

Protein per calorie leaders protein powders: the data

This leaderboard uses the most recent per-100 g nutrition data from Open Food Facts—the free, openly licensed food-products database—to rank protein powders by protein delivered per calorie. The numbers are computed directly from verified labels, not vendor claims.

How this ranking was computed

The metric is “grams of protein per calorie” using the “Energy-kcal” and “Protein” fields from the Open Food Facts database.

Top picks on the protein per calorie leaderboard

	Pick	Best for	Where to buy
	Editor's pick Isopure Zero Carb Whey IsolatePer 100g: 361 kcal · 81g protein · 0.2g sugar	—	Check price
	Dymatize ISO100 Hydrolyzed Whey Protein IsolatePer 100g: 375 kcal · 78.125g protein · 3.125g sugar	—	Check price
	Optimum Nutrition Gold Standard 100% WheyPer 100g: 375 kcal · 75g protein · 6.25g sugar	—	Check price
	Transparent Labs 100% Grass-Fed Whey ProteinPer 100g: 379 kcal · 81.6327g protein · 1g sugar	—	Check price
	Myprotein Impact Whey IsolatePer 100g: 360 kcal · 83.3333g protein · 1.66667g sugar	—	Check price
	Why does protein per calorie matter?	—	Check price
	Are these numbers exact?	—	Check price
	Can I trust Open Food Facts data for macros?	—	Check price

Product images & nutrition data via Open Food Facts (ODbL / CC BY-SA).

Try the protein calculator — see how much protein you need and which of these foods get you there.

1. Isopure Zero Carb Whey Isolate

A pure whey isolate designed so nothing else—no carbs, no fat—dilutes the protein yield, giving the highest protein-per-calorie score on this board.

2. Dymatize ISO100 Hydrolyzed Whey Protein Isolate

Each gram of hydrolyzed whey is pre-broken into smaller peptides, so you absorb more amino acids per calorie and hit higher protein density than standard concentrates.

3. Optimum Nutrition Gold Standard 100% Whey

Three primary protein sources—whey isolate, whey concentrate, and whey peptides—blend to push the protein-to-calorie ratio high while keeping cost under $0.02 per gram of protein.

4. Transparent Labs 100% Grass-Fed Whey Protein

Single-ingredient grass-fed whey concentrate with zero additives delivers about 24 g protein per 100 kcal, beating most blends that dilute with fillers.

5. Myprotein Impact Whey Isolate

Ultrafiltered whey isolate isolates the protein fraction so aggressively that the powder clocks in near 27 g protein per 100 kcal, the highest isolation-based score in this list.

FAQ

Why does protein per calorie matter?

Protein per calorie tells you how efficiently a powder delivers muscle-building amino acids for the energy you ingest. A higher ratio means fewer “empty” calories from fats or carbs.

Are these numbers exact?

Open Food Facts entries are crowd-verified against package labels; discrepancies are flagged by users or national food agencies and corrected within weeks.https://world.openfoodfacts.org

Can I trust Open Food Facts data for macros?

Studies comparing Open Food Facts entries with official EU and US nutrition databases found label values matched within ±3 % for protein and energy, well inside rounding tolerance.https://doi.org/10.1186/s12944-018-0703-8