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Mars fun size
Mars fun size by Mars provides 451 kcal per 100 g, with 57.5 g of sugars and 3.1 g of protein. That is 91% more sugar than the average product in this category. Its Nutri-Score is E. It is listed in the Bars category.
Nutrient levels per 100 g
Levels use UK front-of-pack reference thresholds.
Nutrition facts
Serving size: 1 bar (16 g)
| Nutrient | Per 100 g | Per serving | % DV* | Category avg |
|---|---|---|---|---|
| Calories | 451 kcal | 72 kcal | 432 | |
| Total fat | 16.9 g | 2.7 g | 3% | 20.4 −17% |
| Saturated fat | 8.1 g | 1.3 g | 7% | 7.7 +6% |
| Carbohydrates | 70.6 g | 11.3 g | 4% | 50.1 +41% |
| Total sugars | 57.5 g | 9.2 g | 30.1 +91% | |
| Protein | 3.1 g | 0.5 g | 1% | 11.5 −73% |
| Salt | 0.3 g | 0 g | 0.5 −34% |
*% Daily Value for a serving, based on a 2,000-calorie diet (FDA reference values). Category average across 2570 Bars products on Foodmetria.
Compared with other bars
Bar shows the share of products in this category that contain less of the nutrient.
Product details
- Serving size
- 1 bar (16 g)
- Sold in
- United Kingdom
- Barcode
- 5000159545341
Prices reported by shoppers
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Frequently asked questions
How many calories are in Mars fun size?
Mars fun size contains 451 kcal per 100 g and about 72 kcal per serving (1 bar (16 g)).
How much sugar is in Mars fun size?
Mars fun size has 57.5 g of sugars per 100 g, which is considered high by UK front-of-pack guidelines.
Is Mars fun size healthy?
It has a Nutri-Score of E (A is best, E is worst). Scores describe nutritional quality and processing, not suitability for your individual diet.
Source: Open Food Facts (ODbL). Last updated March 27, 2026. Spotted a mistake? Edit this product on Open Food Facts. Not medical advice — always check the package label.
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