Myprotein vs Optimum Nutrition 2026: Which Is Cheaper?
Myprotein Impact Whey against Optimum Nutrition Gold Standard 100% Whey on cost per 25g of protein at every bag size, protein per scoop, taste and where to buy, using prices and labels checked in September 2026.
Kevin, founder of WheyWise
Quick answer
Myprotein is cheaper than Optimum Nutrition at every bag size, but the gap shrinks as the bags get bigger. Myprotein Impact Whey costs £1.16 per 25g of protein in the 3.6kg bag, against £1.23 for Optimum Nutrition Gold Standard 100% Whey in the 4.53kg tub, both checked 22 September 2026. In smaller packs the gap is wider: £1.27 against £1.89 at around 900g. Optimum Nutrition Gold Standard carries more protein per scoop (24g against 22g) and, in our founder's own taste test, the better chocolate. WheyWise checked every price and label on each brand's website.
Myprotein Impact Whey and Optimum Nutrition Gold Standard 100% Whey are two of the best-known whey powders in the UK: one the budget favourite, the other the long-established premium name. This comparison lines them up at matching bag sizes on cost per 25g of protein, using the one-off price and nutrition label on each brand's own website, checked 22 September 2026.
Is Myprotein cheaper than Optimum Nutrition?
Yes, at every bag size. Myprotein Impact Whey costs £1.16 per 25g of protein in the 3.6kg bag at £119.99, checked 22 September 2026. Optimum Nutrition Gold Standard 100% Whey costs £1.23 per 25g of protein in the 4.53kg tub at £170, checked the same day. That makes Myprotein Impact Whey 6% cheaper per gram of protein in the largest bags.
| Bag size | Myprotein Impact Whey | Optimum Nutrition Gold Standard | Myprotein cheaper by |
|---|---|---|---|
| Around 900g | £1.27 (900g, £32.99) | £1.89 (896g, £50.00) | 32% |
| Around 2.5kg | £1.18 (2.7kg, £91.49) | £1.43 (2.26kg, £98.00) | 18% |
| Largest bag | £1.16 (3.6kg, £119.99) | £1.23 (4.53kg, £170.00) | 6% |
Cost per 25g of protein, one-off prices with no code applied, checked 22 September 2026 on myprotein.com (Vanilla) and optimumnutrition.com (Double Rich Chocolate; the 896g pack is Extreme Milk Chocolate, the only flavour sold at that size). Live prices for both are on the Optimum Nutrition vs Myprotein comparison.
The pattern is clear: the smaller the bag, the bigger Myprotein's lead. If you buy around 900g at a time, Myprotein Impact Whey is 32% cheaper per gram of protein. If you buy Optimum Nutrition Gold Standard in the 4.53kg tub, the premium almost disappears.
Cheaper per gram of protein
MyProtein Impact Whey Protein Powder
1kg bag
The cheaper whey of the two at every size, and the easy pick if you buy smaller bags.
or compare all UK prices →Cheaper per gram of protein
Pros
- + £1.16 per 25g of protein in the 3.6kg bag, checked 22 September 2026
- + 32% cheaper per gram of protein than Optimum Nutrition in ~900g packs
- + More than 40 flavours and frequent sitewide sales
Cons
- – Contains 72g to 75g of protein per 100g, less than Gold Standard
- – List prices are high, so it is best bought during a sale
●Nutrition per scoop · 21.6g protein in 30g▼
Protein makes up 72%
of this 30g scoop · 113 kcal total
Which has more protein per scoop?
Optimum Nutrition Gold Standard 100% Whey has more. Optimum Nutrition Gold Standard 100% Whey Double Rich Chocolate contains 76g of protein per 100g, which is 24g of protein in a 31g scoop, with 116 kcal and 1.0g of sugar per scoop. Myprotein Impact Whey contains 72g of protein per 100g in Vanilla, 73g in Chocolate Smooth and 75g in Unflavoured, which is 22g to 23g of protein in a 30g scoop, according to the labels on each brand's website on 22 September 2026.
| Per scoop | Myprotein Impact Whey (Vanilla, 30g) | ON Gold Standard (Double Rich Chocolate, 31g) |
|---|---|---|
| Protein | 22g | 24g |
| Calories | 114 kcal | 116 kcal |
| Sugar | 1.5g | 1.0g |
| Protein per 100g | 72g | 76g |
The difference is small, and the cost per 25g of protein figures above already allow for it, so it does not change which is cheaper.
Which tastes better, Myprotein or Optimum Nutrition?
In our founder's own taste test, Optimum Nutrition Gold Standard in Double Rich Chocolate came out ahead. He ranks it second of everything he drinks: it mixes very well, tastes of real chocolate and is not too thick with water. Myprotein Impact Whey came third, best in Salted Caramel, which Myprotein does very well. Both were tried with water only. Taste is personal, so read the full ranking in our best tasting protein powder guide.
More protein per scoop
Optimum Nutrition Gold Standard 100% Whey Protein
896g bag
The premium pick for taste and protein per scoop, and close on price if you buy the big tub.
Buy Gold Standard 100% Whey Protein →See the price on AmazonMore protein per scoop
Pros
- + Contains 76g of protein per 100g, 24g in a 31g scoop
- + Double Rich Chocolate ranked second in our founder's taste test
- + £1.23 per 25g of protein in the 4.53kg tub, only 6% more than Myprotein's largest bag
Cons
- – £1.89 per 25g of protein in the 896g pack, 49% dearer than Myprotein at that size
- – Fewer bag sizes and flavours than Myprotein
●Nutrition per scoop · 23.6g protein in 31g▼
Protein makes up 76%
of this 31g scoop · 114 kcal total
Which has more flavours and bag sizes?
Myprotein wins on choice. Myprotein Impact Whey has more than 40 flavours on myprotein.com, in packs from 15 to 120 servings. Optimum Nutrition Gold Standard 100% Whey is sold on optimumnutrition.com in 310g, 465g, 620g, 899g, 2.26kg and 4.53kg sizes, checked 22 September 2026, with fewer flavours. If you want variety, Myprotein is the better bet.
Where is each cheapest to buy?
Myprotein is cheapest bought direct during one of its frequent sales. On 22 September 2026, myprotein.com was taking an extra 10% off all protein powders in the basket. Optimum Nutrition Gold Standard 100% Whey Double Rich Chocolate cost £98.00 for 2.26kg both on optimumnutrition.com and on Amazon UK, sold by Amazon, on the same day, so there was no saving either way at that size. The 4.53kg tub at £170 on optimumnutrition.com was the cheapest way to buy it per gram of protein. For more ways to cut the cost, see our guide to the cheapest Gold Standard whey in the UK.
Should you buy Myprotein or Optimum Nutrition?
Buy Myprotein Impact Whey if price per gram of protein matters most, especially if you buy smaller bags: it is 32% cheaper per gram of protein at around 900g, checked 22 September 2026. It also has far more flavours to choose from.
Buy Optimum Nutrition Gold Standard 100% Whey if you want the most protein per scoop and a chocolate that tastes of real chocolate, and buy the 4.53kg tub, where it costs only 6% more per gram of protein than Myprotein. For a detailed look at the two formulas, see our Impact Whey vs Gold Standard review, and for cheaper brands to consider, read Optimum Nutrition alternatives UK and Protein Works vs Myprotein.
Frequently asked questions
Is Myprotein cheaper than Optimum Nutrition?
Yes, at every bag size we checked. Myprotein Impact Whey costs £1.16 per 25g of protein in the 3.6kg bag, against £1.23 for Optimum Nutrition Gold Standard 100% Whey in the 4.53kg tub, both checked 22 September 2026. The gap is widest in small packs: £1.27 against £1.89 at around 900g.
Which has more protein, Optimum Nutrition Gold Standard or Myprotein Impact Whey?
Optimum Nutrition Gold Standard 100% Whey. Double Rich Chocolate contains 76g of protein per 100g, which is 24g in a 31g scoop. Myprotein Impact Whey contains 72g to 75g per 100g depending on flavour, which is 22g to 23g in a 30g scoop. Our cost per 25g of protein figures already allow for the difference.
Is Optimum Nutrition Gold Standard worth the extra money?
In the biggest tubs the premium is small. Optimum Nutrition Gold Standard costs £1.23 per 25g of protein in the 4.53kg tub, only 6% more than Myprotein Impact Whey in its 3.6kg bag, checked 22 September 2026. In smaller packs it costs up to 49% more, so it is best value bought big.
Does Optimum Nutrition taste better than Myprotein?
Taste is personal, but in our founder's own taste test Optimum Nutrition Gold Standard in Double Rich Chocolate ranked above Myprotein Impact Whey, which he rated best in Salted Caramel. Both were tried with water. Our best tasting protein powder guide has the full ranking.
Is Optimum Nutrition cheaper on Amazon?
Not when we checked. Optimum Nutrition Gold Standard 100% Whey Double Rich Chocolate cost £98.00 for 2.26kg both on optimumnutrition.com and on Amazon UK, sold by Amazon, on 22 September 2026. The 4.53kg tub on optimumnutrition.com at £170 was the cheapest per gram of protein.
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