Decathlon whey review: well rated, but expensive per kilo of protein

In summary

Decathlon whey is well rated (4.2 out of 5 for the concentrate, 4.5 for the isolate) and sweetened with stevia, but its concentrate contains only 70% protein, cut with skimmed milk. It works out at 56.18 EUR per kilo of protein in the 1.5 kg size, 27% more than the cheapest concentrate in our price checks; its isolate, at 66.38 EUR, costs 21% more than the Nutripure isolate in 4 kg. Fine for a first tub, not for the long run.

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The short answer

Decathlon’s whey is decent, well rated and sweetened with stevia rather than sucralose, but it is not cheap once converted to a per-kilo-of-protein price: its concentrate contains only 70% protein, because it is cut with skimmed milk powder. The result: 56.18 EUR per kilo of protein in the 1.5 kg size, when the cheapest concentrate in our price checks is at 41.23 EUR. Its isolate does better on content (82%) but costs 66.38 EUR per kilo of protein, 21% more than the cheapest isolate we have recorded.

What our price checks found

Product and size Protein / 100 g Price Price / kg of protein
Decathlon Whey protein, 1.5 kg 70 g 58.99 EUR 56.18 EUR
Decathlon Whey protein, 900 g 70 g 38.99 EUR 61.89 EUR
Decathlon Pure whey 100% isolate, 900 g 82 g 48.99 EUR 66.38 EUR
Prices, nutritional values (chocolate flavour) and ingredients taken from decathlon.fr on 23/10/2026. Price per kilo of protein = price of the size / weight / protein content.
Benchmark from our price checks Price / kg of protein Against Decathlon
Nutrimuscle Whey Native concentrate, 4 kg 41.23 EUR 27% less than the Decathlon concentrate in 1.5 kg
Nutrimuscle Whey Native concentrate, 1 kg 47.44 EUR 23% less than the Decathlon concentrate in 900 g
Nutripure Native Whey Isolate, 4 kg 54.69 EUR 18% less than the Decathlon isolate
Myprotein Impact Whey, 3.6 kg on promotion 54.01 EUR 4% less than the Decathlon concentrate in 1.5 kg
Nutri&Co native whey concentrate, 900 g 60.15 EUR 3% less than the Decathlon concentrate in 900 g
Nutrimuscle and Nutri&Co: recorded on 23/09/2026. Nutripure and Myprotein: recorded on 23/10/2026. Details in our whey comparison.

Where Decathlon whey is good

The sweetener. Both of its wheys are sweetened with steviol glycosides, whereas part of the market, Myprotein first among them, uses sucralose. If you avoid synthetic sweeteners, that is a real plus.

Customer reviews. 4.2 out of 5 for the concentrate (5,889 reviews on the 900 g) and 4.5 out of 5 for the isolate (5,676 reviews), posted on Decathlon’s website. At that volume, it is solid. These reviews mostly concern taste and mixability: they say people like the product, not that it is well priced.

Availability. In store, with no delivery charge or minimum order: for a first tub or a stopgap, it is convenient.

Where it is too expensive

The concentrate is diluted. Its ingredients list puts skimmed milk powder right after the whey concentrates (90%), and the result shows in the nutrition table: 70 g of protein and 17 g of carbohydrate per 100 g, against 80 g of protein for a native whey concentrate such as Nutrimuscle’s. With tubs at a similar price, you therefore pay more for every gram of protein.

Large sizes are missing. Decathlon stops at 1.5 kg for the concentrate and 900 g for the isolate. Yet size is what sets the price of a whey: at Nutrimuscle and Nutripure, the 4 kg tubs come in 13 to 21% below their small sizes.

The isolate is pricey. 66.38 EUR per kilo of protein, for a product with 82% protein and soya lecithin. Nutripure’s native isolate, at 86.8 g of protein per 100 g, costs 54.69 EUR in the 4 kg tub, 18% less; in the 750 g pouch, it goes back up to 68.97 EUR, slightly above Decathlon.

Who it suits, in practice

Yes for a first tub, bought in store, if you want to try whey without ordering online, and if you prefer stevia to sucralose.

No for regular use. At 25 g of protein a day, the Decathlon concentrate in 1.5 kg costs 513 EUR a year, against 376 EUR for Nutrimuscle’s concentrate in 4 kg. For an isolate, Nutripure in 4 kg costs 499 EUR against 606 EUR at Decathlon. The alternatives are detailed in our whey comparison, and the brands in our reviews of Nutripure and Myprotein.

How we put this review together

We have not tested these products and we do not claim to. Prices, nutrition tables and ingredients lists were taken from decathlon.fr on 23/10/2026, then converted to a price per kilo of protein, the only way to compare powders with different protein contents. The benchmarks come from the price checks in our whey comparison. The ratings quoted are those on Decathlon’s website: they measure satisfaction (taste, texture), not composition or price.

Our sources

  • Official decathlon.fr pages (Whey protein 900 g and 1.5 kg, Pure whey 100% isolate 900 g), consulted on 23/10/2026: prices, nutritional values, ingredients, customer ratings.
  • Our Nutrimuscle and Nutri&Co price checks of 23/09/2026, Nutripure and Myprotein of 23/10/2026.

Frequently asked questions

Is Decathlon whey good?

It is well rated by its customers (4.2 out of 5 across nearly 5,900 reviews) and sweetened with stevia. But its concentrate contains only 70% protein, because it is cut with skimmed milk powder, which makes it expensive per kilo of protein.

How much does Decathlon whey cost per kilo of protein?

56.18 EUR in 1.5 kg and 61.89 EUR in 900 g for the concentrate, 66.38 EUR for the 900 g isolate (recorded on 23/10/2026). The cheapest concentrate in our price checks is at 41.23 EUR, the cheapest isolate at 54.69 EUR.

Which whey should you choose instead?

A native concentrate in a large size, such as Nutrimuscle’s in 4 kg (41.23 EUR per kilo of protein), or an isolate if you digest lactose poorly, such as Nutripure’s in 4 kg (54.69 EUR).

Whey or isolate at Decathlon?

The isolate contains 82% protein against 70%, and costs only 7% more per kilo of protein than the 900 g concentrate. If you digest lactose poorly, it is the one to take.