How many slices is 400g of bread? The surprising answer

December 2, 2025 •

3 min read

According to one brand's label, a 400g loaf of medium wholemeal bread can contain approximately 17 slices. However, the exact answer to how many slices is 400g of bread depends heavily on the type of bread, its density, and the slice thickness.

Quick Summary

The quantity of slices in a 400g loaf varies by bread type and slice thickness. Denser, wholemeal varieties yield fewer, thicker slices than lighter white loaves.

Key Points

Significant Variation: The number of slices in a 400g loaf can range dramatically, from as few as 8 to over 17, depending on the bread's characteristics.
Density is Key: Denser breads like wholemeal have fewer, thicker slices for the same 400g weight compared to lighter, more aerated white bread.
Slice Thickness Matters: How thick the bread is cut, whether by a manufacturer or at home, directly influences the final slice count.
Check the Label: For accurate dietary tracking, always refer to the 'per slice' weight or nutritional information on the product label, as slice weight varies widely.
Commercial vs. Homemade: Factory-sliced loaves are typically consistent, while homemade bread allows for custom slice thickness and therefore a variable slice count.
Informed Shopping: Knowing the slice variation helps consumers better predict how long a loaf will last and manage their nutritional intake effectively.

The question of how many slices is 400g of bread might seem simple, but the reality is more complex than a single number. The exact slice count is influenced by several key factors that affect the bread's volume and density. A consumer's typical experience might see a range from as few as 8 to as many as 17 or more slices in a 400g loaf. Understanding these variables is key to knowing what to expect from your next loaf.

The Factors Influencing Bread Slice Count

Bread Type and Density

The density of bread is arguably the most significant factor affecting slice count. Different flours and baking methods result in vastly different textures and weights per volume. Denser breads, such as wholemeal, sourdough, or artisanal varieties, pack more mass into the same space as a lighter white loaf. This higher density means that to reach a 400g weight, the loaf will have a smaller volume and therefore fewer slices. In contrast, commercially produced white bread often has a more aerated crumb structure, leading to a larger loaf for the same weight and a higher slice count.

Slice Thickness

Manufacturers and home bakers can control the thickness of each slice, which directly impacts the final count. Historically, a transition from 500g to 400g loaves saw a decrease in the number of slices. A loaf designed for thick-cut toast will have fewer slices than one intended for delicate sandwiches, even if the total weight is identical. For example, some wholemeal loaves are explicitly cut thicker to prevent them from breaking, reducing the overall slice number. For those who slice bread at home, a simple slicing guide can ensure consistency, though the final count is a function of both the loaf's density and the chosen thickness.

The Baking Process and Ingredients

Beyond flour type, the baking process itself plays a crucial role. The 'oven spring'—the final rise of the dough in the oven—affects the final volume and texture. A good oven spring creates a lighter, more voluminous crumb, potentially increasing the slice count for a given weight. Factors like dough hydration, gluten content, and fermentation time all contribute to the final crumb structure. A dough with a higher hydration level and robust gluten network tends to produce a bread with a larger internal structure and lower density.

Average Slices in a 400g Loaf: A Comparison

This table provides a general comparison of how different bread types influence the slice count in a 400g loaf.


Bread Type	Approximate Slices (400g Loaf)	Average Slice Weight (g)
Wholemeal/Whole-wheat	8–10	40–50
White (commercial)	16–17	~23–25
Multigrain	~15	~26.7
Sourdough (Dense)	Fewer than white	~32

What Does This Mean for Your Shopping and Recipes?

Understanding the variation in a 400g loaf's slice count is valuable for both nutrition tracking and meal planning. When following a recipe that specifies a number of slices, or counting carbohydrate portions, it is always more accurate to use the weight per slice listed on the nutrition label rather than assuming a standard slice weight. For instance, a 40g wholemeal slice has significantly more calories and carbohydrates than a 25g white slice. Being mindful of these differences ensures greater accuracy in managing dietary intake. Furthermore, it helps avoid misjudging how long a loaf will last based solely on its total weight.

Conclusion

The question of how many slices is 400g of bread has no single answer. The number is a variable result of the bread's type, density, and the chosen thickness of each slice. From a dense wholemeal loaf yielding around 8-10 thick slices to a lighter white loaf providing 16-17 or more, the variation is significant. This knowledge is not just trivia; it is practical information that can help with accurate meal preparation and understanding nutritional content. Always check the label for the most precise information regarding slice weight and nutritional value.

For more detailed nutritional information on bread types and portion sizes, consult resources like the NHS, which offers valuable dietary guidance. South Tees Hospitals NHS Foundation Trust provides insights into carbohydrate content that can help with meal planning.

Frequently Asked Questions

A 400g loaf of commercially produced white bread can yield approximately 16 to 17 slices. This is based on an average slice weight of around 23 to 25 grams for many brands.

A 400g loaf of wholemeal bread typically contains fewer slices than a white loaf, often around 8 to 10. This is because wholemeal slices are generally cut thicker and the bread is denser.

The variation is mainly due to three factors: the bread type (which affects density), the thickness of each slice, and the baking process. Denser breads and thicker cuts result in fewer slices.

Yes, it does. A slice of denser wholemeal or artisan bread is usually heavier than a standard commercial slice of white bread, even if they appear to be a similar size.

The average weight of a slice of bread varies significantly by type. A standard commercial white slice is often around 25g, while a thicker wholemeal slice can be 40g or more.

For precision, it is always better to count carbohydrates based on the gram weight listed on the nutrition label. This is because slice sizes and weights can vary considerably between brands and bread types.

For factory-sliced loaves, the count is pre-determined. If baking or slicing at home, you can achieve a specific number by using a bread slicing guide or a measuring tool to ensure consistent slice thickness.