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ANABOLIC Whey Matrix97 bought this week
97bought this week80.86% protein · 24.3g / 25g serving
Bag · 5kg
£39.99
£0.25 / 25g protein
Mass Gainer
Cheapest Mass Gainer UK
Compare protein prices from MyProtein, Bulk, Optimum Nutrition and 85+ other UK retailers. Every product ranked by cost per 25g of protein. Free, updated weekly. Whether you are buying whey concentrate, whey isolate, vegan protein, casein, or a mass gainer, every bag is normalised to the same metric so you can compare across brands, sizes, and protein percentages without doing the maths yourself. No sponsored rows, no affiliate-biased rankings. The cheapest option sits at the top because it is the cheapest, not because a brand paid for placement.
79products tracked
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Hand-picked by our nutrition team every Monday, 07:00. Scored on £/25g protein, clean-label, and weekly velocity.
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About Mass Gainer Protein
Mass gainers combine protein with high amounts of carbohydrates and calories, designed for people who struggle to eat enough to support muscle growth. A typical serving can contain 300-500+ calories alongside 20-40g of protein.
We track mass gainer products across UK retailers, sorted by price per 100g. Because serving sizes and calorie content vary enormously between brands, comparing by weight gives you a much clearer picture of value than comparing by serving.
Mass gainers are most useful if you have a fast metabolism, struggle to eat large meals, or are in a dedicated bulking phase. If your goal is lean muscle without excess calories, a standard whey protein with a separate carbohydrate source may be more cost-effective and flexible.
Methodology
How we rank every bag.
Independent, transparent, and updated weekly. Here's what goes into each score.
01
Cost normalised to £/25g
Every bag divided by its true protein weight, so you see the real cost of a scoop across any size or brand.
02
Protein quality, not just %
Protein %, leucine and digestibility feed the Performance score. A 90% isolate and a 90% vegan blend are not the same.
03
Clean-label audit
Ingredient count, artificial sweeteners, added sugars, third-party certifications. 0 to 100 score.
04
Social and review signals
Weekly purchase volume and weighted review scores surface what people actually re-buy, not just what ranks on search.
Questions, answered.
Most mass gainers provide 300-1200 calories per serving depending on the product. They typically combine whey protein with maltodextrin or oat flour for the calorie content.