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.

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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
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.

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.