Best Whey Protein Powder (2026)

Concentrate, blend or isolate: which whey should you buy?

Pick by lactose and label, then compare cost. Isolates have less lactose and cost about 9% more per 25 g at the median, or 18 cents, but the ranges overlap.

Filtering matters less for protein than the labels suggest. Naked Whey, a concentrate, is 83% protein by weight, the same as BulkSupplements, an isolate (83%). The flavored two are lower: Gold Standard 79% and ISO100 78%. Compare grams of protein a serving, not the word “isolate” on the tub.

Is whey protein powder safe?

Whey is milk protein, a common food. How much lead you get depends on the brand, and for most of these powders no number is published. Three things to know.

Lead

Whey tests lower in lead than plant powders. A 2025 Clean Label Project study of 160 powders found 28% of whey powders over California’s Prop 65 lead level, against 77% of plant powders. Consumer Reports tested two whey tubs by name: Gold Standard at 56% of the daily lead limit Consumer Reports uses (it said 1 to 2 servings a day is fine) and Momentous Whey Protein Isolate at 30% (3 servings a day). It did not test Naked Whey. Some brands also post a lab report for each batch, and the table shows those numbers for the flavor we link. We found a lead number for 3 of the 22 powders. A missing number is not a bad one.

Milk allergy

Whey is milk protein. If you have a milk allergy, skip all whey; see the best plant-based protein powder.

Kidneys

If you have kidney disease, ask your doctor before adding protein powder.

Which whey is best if you are sensitive to lactose?

Start with an isolate, such as BulkSupplements Whey Protein Isolate, because it is filtered to remove most of the lactose. Isolates still hold a little lactose, so they are not lactose-free. If one still bothers you, try a plant powder. See the best whey isolate and the best lactose-free protein powder.

Is grass-fed whey worth the extra cost?

It is worth it if you care how the cows were fed, and it will not change the protein on the label. Grass-fed is the brand’s claim, not a test result. Naked Whey, the grass-fed pick here, has 25 g of protein a serving against 24 g for Gold Standard. See the best grass-fed whey isolate.

Flavored or unflavored whey?

Pick unflavored if you mix whey into food, and flavored if you drink it plain. The unflavored picks here, Naked Whey and BulkSupplements, list no sweetener. Gold Standard uses ace-K, and ISO100 uses sucralose and stevia. 11 of the 22 use sucralose or ace-K, so check the table if you avoid them. See the best unflavored whey.

How much whey protein should you take a day?

One or two scoops is plenty for most people, which is 25 to 50 g of protein. Powder fills gaps; most of your protein should still come from food. For people lifting weights, muscle gains stopped rising above about 1.6 g of protein per kg of body weight a day, counting food (Morton 2018). Work out your own number.

Questions people ask

How we picked

We priced all 22 whey powders in our catalog on Amazon on November 6, 2026, one tub per product, and read each label for the flavor we link to set its kind. A label that lists isolate and concentrate together counts as a blend. We left out powders that mix in other proteins, such as Muscle Milk and Garden of Life Sport Whey, and ready-to-drink shakes. The medians compare 14 isolates with 6 concentrates and blends; hydrolyzed isolates are separate. Testing lists were checked August 25, 2026 to September 22, 2026. For the other picks, see the best protein powder, or compare two common tubs in Optimum Nutrition vs Dymatize ISO100.