Head to head · Protein Powder
Optimum Nutrition Gold Standard 100% Whey vs Transparent Labs 100% Grass-Fed Whey Protein Isolate
Transparent Labs scores higher overall (8.8 vs 8.7 out of 10), mainly on quality & purity and transparency. Optimum Nutrition still leads on value and experience.
Updated September 2026 from our full reviews · How we score
The benchmark whey blend: 24 g of protein per 120-calorie scoop, Informed Choice certified, and a flavor lineup few rivals can match.
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A grass-fed whey isolate with 28 g of protein per scoop, stevia instead of artificial sweeteners, and NSF Certified for Sport status.
We may earn a commission when you buy through these links — it never affects our scores. How we make money
We may earn a commission when you buy through these links — it never affects our scores. How we make money
The short answer
Choose Optimum Nutrition if…
- First-time protein powder buyers
- Everyday post-workout shakes
- Drug-tested athletes who want a certified product
- People who like lots of flavor choice
- You care most about value, experience
Choose Transparent Labs if…
- Drug-tested athletes
- Clean-label shoppers avoiding artificial sweeteners
- People who want grass-fed sourcing
- Lactose-sensitive lifters
- You care most about quality & purity, transparency
Side by side
| Gold Standard 100% Whey | 100% Grass-Fed Whey Protein Isolate | |
|---|---|---|
| Our score | 8.7 / 10 | 8.8 / 10 |
| Efficacy (30%) | 8.8 | 9.1 |
| Quality & Purity (25%) | 9.0 | 9.4 |
| Value (20%) | 8.3 | 7.4 |
| Experience (15%) | 9.0 | 8.6 |
| Transparency (10%) | 8.0 | 9.5 |
| Form | Powder | Powder |
| Serving | 1 scoop (31 g)74 servings per container | 1 scoop (34.9 g)30 servings per container |
| Price per serving | See retailer | $2.17 |
| Testing & certifications | Informed Choice | NSF Certified for SportInformed Choice |
| Dietary | Gluten-free | Gluten-free |
| Key ingredients |
|
|
| Flavors | 8 (Double Rich Chocolate, Extreme Milk Chocolate, Vanilla Ice Cream…) | 8 (Milk Chocolate, French Vanilla, Dark Chocolate…) |
| Creator video reviews | 5 | 5 |
Pros and cons
Gold Standard 100% Whey
- 24 g of protein in a 120-calorie, 31 g scoop (about 77% protein by weight)
- Informed Choice certified and regularly tested for banned substances
- More than 20 flavors on the brand's US store, with consistently strong feedback on taste and mixability
- Fully disclosed ingredient list with no proprietary blend
- Widely available on Amazon, TikTok Shop and at major retailers
- Sweetened with acesulfame potassium and uses artificial flavors
- Contains whey concentrate, and a share of buyers report digestive discomfort
- No longer cheap: about $1.39 per serving at typical retail prices for the 5 lb tub, and the brand-site list price is higher
- Servings per tub vary by flavor (roughly 68 to 75 in 5 lb-class tubs), which complicates price comparisons
100% Grass-Fed Whey Protein Isolate
- 28 g of protein per scoop from grass-fed whey isolate
- Listed in NSF's Certified for Sport database and certified by Informed Choice (per the brand)
- Every ingredient disclosed by weight, with batch test results published online
- No artificial sweeteners, dyes or preservatives
- buyers frequently describe it as easy on the stomach
- About $2.17 per serving for the 30-serving tub, well above whey blends
- Stevia can leave an aftertaste some people dislike
- Made on equipment that also processes eggs, soy, wheat, shellfish, fish oil, tree nuts and peanut oil, and some flavors contain peanuts
- Mostly sold through the brand site and Amazon, so in-store discounts are rare
Our verdicts
Gold Standard 100% Whey
Gold Standard 100% Whey remains a default recommendation for good reason: a lean 24 g protein dose, banned-substance certification, and taste and mixability endorsed across about 100,000 buyer ratings. It is no longer a bargain, and the concentrate and artificial sweetener will not suit everyone, but few powders balance quality, variety and availability this well.
Full review
100% Grass-Fed Whey Protein Isolate
For shoppers who prioritize ingredient transparency and third-party verification, this is one of the strongest whey isolates available: 28 g of protein, a short stevia-sweetened ingredient list, NSF Certified for Sport status and public batch testing. The trade-off is price, at more than $2 per serving, and stevia's flavor will not suit everyone.
Full review
What creators say
Questions people ask
Is Optimum Nutrition better than Transparent Labs?
Are Optimum Nutrition and Transparent Labs third-party tested?
Who should choose Optimum Nutrition over Transparent Labs?
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