Best protein powders, ranked by leucine

Every isolate scores Platinum on density alone — so we rank by leucine per serving, the metric that actually decides whether one scoop triggers muscle protein synthesis.

Powder isn't always the cheapest protein, either — see how it stacks up against eggs, milk, and chicken in our cheapest-protein-per-gram ranking.

Filter:

Product	Protein / svg	Leucine	DAY	Density	Quality
Nutricost Whey Protein Isolate whey isolate Sucralose	30g 130 kcal	3.15g ✓ MPS (est.)	30.0g 100% effective	92.3% Platinum	Complete
Transparent Labs 100% Grass-Fed Whey Protein Isolate whey isolate Stevia Informed ⬡ Heavy-metal tested	28g 120 kcal	2.94g ✓ MPS (est.)	28.0g 100% effective	93.3% Platinum	Complete
BulkSupplements Whey Protein Isolate 90% whey isolate Unsweetened	27g 115 kcal	2.84g ✓ MPS (est.)	27.0g 100% effective	93.9% Platinum	Complete
NOW Sports Whey Protein Isolate whey isolate Stevia Informed Sport	25g 100 kcal	2.7g ✓ MPS	25.0g 100% effective	100% Platinum	Complete
Dymatize ISO100 Hydrolyzed 100% Whey Isolate whey isolate Artificial blend Informed	25g 130 kcal	2.7g ✓ MPS	25.0g 100% effective	76.9% Platinum	Complete
Naked Nutrition Naked Whey whey concentrate Unsweetened NSF ⬡ Heavy-metal tested	25g 120 kcal	2.6g ✓ MPS	25.0g 100% effective	83.3% Platinum	Complete
Optimum Nutrition Gold Standard 100% Whey whey blend Acesulfame-K	24g 120 kcal	2.5g ✓ MPS	24.0g 100% effective	80% Platinum	Complete
Dymatize Elite Casein casein Artificial blend Informed	25g 130 kcal	2.5g ✓ MPS	25.0g 100% effective	76.9% Platinum	Complete
Naked Nutrition Naked Casein casein Unsweetened NSF ⬡ Heavy-metal tested	26g 110 kcal	2.47g Below MPS (est.)	26.0g 100% effective	94.5% Platinum	Complete
NOW Sports Whey Protein Concentrate, Unflavored whey concentrate Unsweetened Informed Sport	24g 130 kcal	2.47g Below MPS	24.0g 100% effective	73.8% Platinum	Complete
BulkSupplements Whey Protein Concentrate 80% whey concentrate Unsweetened	23g 120 kcal	2.43g Below MPS	23.0g 100% effective	76.7% Platinum	Complete
Vega Sport Premium Protein plant blend Stevia NSF CSF	30g 170 kcal	2.34g Below MPS (est.)	24.6g 82% effective	70.6% Platinum	Complete (mod.)
Garden of Life Sport Organic Plant-Based Protein plant blend Stevia NSF CSF	30g 170 kcal	2.34g Below MPS (est.)	24.6g 82% effective	70.6% Platinum	Complete (mod.)
Legion Whey+ whey isolate Stevia	22g 120 kcal	2.31g Below MPS (est.)	22.0g 100% effective	73.3% Platinum	Complete
Optimum Nutrition Gold Standard 100% Casein casein Artificial blend	24g 120 kcal	2.3g Below MPS	24.0g 100% effective	80% Platinum	Complete
Quest Nutrition Multi-Purpose Protein Powder milk blend Unsweetened	24g 100 kcal	2.28g Below MPS (est.)	24.0g 100% effective	96% Platinum	Complete
Ascent Native Fuel Micellar Casein casein Unsweetened Informed Sport	25g 110 kcal	2.2g Below MPS	25.0g 100% effective	90.9% Platinum	Complete
NOW Sports Pea Protein pea Stevia Informed Sport	24g 100 kcal	1.97g Below MPS	19.7g 82% effective	96% Platinum	Complete (mod.)
Transparent Labs Organic Vegan Rice & Pea Protein plant blend Stevia Informed ⬡ Heavy-metal tested	24g 150 kcal	1.97g Below MPS (est.)	19.7g 82% effective	64% Platinum	Complete (mod.)
Ka'Chava Whole Body Meal Shake plant blend Monk fruit	25g 240 kcal	1.95g Below MPS (est.)	20.0g 80% effective	41.7% Platinum	Complete (mod.)
NOW Sports Micellar Casein casein Unsweetened Informed Sport	19g 90 kcal	1.81g Below MPS (est.)	19.0g 100% effective	84.4% Platinum	Complete
Truvani Plant Based Protein plant blend Monk fruit	20g 130 kcal	1.64g Below MPS (est.)	16.4g 82% effective	61.5% Platinum	Complete (mod.)
Orgain Organic Protein plant blend Stevia	21g 150 kcal	1.64g Below MPS (est.)	17.2g 82% effective	56% Platinum	Complete (mod.)
NOW Sports Soy Protein Isolate soy Unsweetened Informed Sport	20g 90 kcal	1.6g Below MPS (est.)	18.0g 90% effective	88.9% Platinum	Complete (mod.)
KOS Organic Plant Protein plant blend Natural blend ⬡ Heavy-metal tested	20g 170 kcal	1.56g Below MPS (est.)	16.4g 82% effective	47.1% Platinum	Complete (mod.)
Sunwarrior Warrior Blend Organic plant blend Stevia	18g 100 kcal	1.48g Below MPS (est.)	14.8g 82% effective	72% Platinum	Complete (mod.)

Sorted by leucine per serving (descending), then density. Leucine values marked (est.) are computed from protein-source factors when no labeled aminogram is published; values without (est.) are taken from manufacturer aminograms. The DAY column is effective protein after digestion (label protein × DIAAS, clamped — DIAAS > 1 doesn't add grams). Cert chips link to the certification legend.

Whey

Best whey protein

Isolate, concentrate, hydrolyzed — ranked by leucine.

Casein

Best casein protein

Slow-digesting micellar casein — pre-bed picks.

Plant

Best vegan protein

Pea, soy, blended — leucine fractions and MPS dosing.

Stirring a scoop into food instead of water? See how yogurts compare on protein or which protein cereals actually deliver.

Choosing between whey and casein? See our whey vs casein comparison for the density, leucine, and DIAAS numbers side by side.

Wondering if isolate is worth the extra money? See whey isolate vs concentrate — one brand's two formats, label-measured on both sides.

Frequently asked questions

What's the best protein powder for building muscle?

For pure muscle-protein synthesis triggering, the best protein powder is the one that clears the 2.5g leucine threshold per serving — Dymatize ISO100, NOW Sports Whey Isolate, and Optimum Nutrition Gold Standard all clear it at one scoop. Plant powders typically require 1.5 scoops to clear it because pea/rice leucine fractions are lower than whey.

Are protein powders worth the cost?

For 25g of high-quality protein, bulk whey isolate ($25–55 per 5lb tub) usually lands at $0.20–0.50 per 10g protein — competitive with chicken breast, cheaper than eggs at most supermarket prices. The "premium" tier is hydrolyzed isolate, grass-fed lines, and certified-for-sport tubs (NSF, Informed-Sport), which run $0.50–1.00 per 10g. Use the protein-per-dollar calculator to compare with your actual prices.

Whey vs casein vs plant protein — what should I pick?

Whey is fastest-digesting and highest-leucine — best for post-workout and breakfast. Casein digests slowly (3–7 hours) — best pre-bed to extend overnight amino acid release. Plant protein (pea, soy, or blends) works for muscle building if you hit the leucine threshold (often needs slightly larger servings); also the right call for vegans/lactose-intolerant.

Why is leucine more important than total protein on a powder label?

Leucine is the amino acid that signals MPS activation — total protein is the substrate, leucine is the trigger. A casein scoop with 25g protein but only 2.3g leucine misses the MPS trigger at 1 serving, while a whey isolate scoop with the same 25g protein and 2.7g leucine clears it. Per-scoop leucine, not per-scoop protein, is the right comparison axis for muscle building.