How much does 1 walnut weigh in grams?

December 10, 2025 •

2 min read

Research indicates that the average weight of a single walnut in its shell is about 11.7 grams. However, the weight varies, depending on factors such as the walnut variety and whether the shell is included.

Quick Summary

One in-shell walnut averages 11.7 grams, but this can vary. A shelled walnut kernel usually weighs 40-50% of the total, approximately 4-6 grams per nut.

Key Points

In-shell Average: A single in-shell walnut typically weighs about 11.7 grams, but this can vary by variety and growing conditions.
Shelled Weight: A shelled walnut kernel weighs significantly less, usually comprising 40-50% of the total in-shell weight, or approximately 4-6 grams per nut.
Contributing Factors: Weight is influenced by the walnut's variety, its moisture content, and environmental factors, leading to natural variations.
Serving Size: A standard nutritional serving is one ounce (about 28 grams) of shelled walnuts, which is roughly 5-6 whole kernels or 12-14 halves.
Nutritional Density: Despite being high in calories, walnuts are nutrient-dense, providing healthy fats, protein, and antioxidants, and a small number of nuts satisfies a standard portion.
Practical Usage: For cooking and nutrition, it's most practical to use standard serving sizes or measure shelled kernels, as they are the edible part of the nut.

The Average Weight of a Single Walnut

While the weight of a single walnut varies naturally, agricultural studies provide average figures. Research indicates that the average weight of a single in-shell walnut can range from approximately 9.8 grams to over 16 grams, with one study finding an average of 11.7 grams. This variation depends on factors like genotype and environmental conditions, making standard serving sizes more practical for cooking or dietary planning than weighing individual nuts.

Shelled vs. Un-shelled: The Weight Difference

The distinction between in-shell and shelled walnuts is crucial for weight. The inedible shell constitutes a significant portion of the total weight, with the edible kernel making up about 40-50%. Consequently, a typical 11.7-gram in-shell walnut would yield a kernel weighing between 4.7 and 5.9 grams. The kernel-to-shell ratio is also affected by the walnut variety, with thin-shelled types having a higher percentage of kernel. Recipes usually refer to shelled kernels, making this conversion important.

Factors Influencing Walnut Weight

Several elements contribute to the weight of an individual walnut:

Walnut Variety: Different cultivars have distinct size and weight characteristics.
Moisture Content: Walnut weight changes with moisture levels, with dried nuts weighing less than fresh ones.
Growing Conditions: Environmental factors impact tree health and nut size.
Fruit Load: A larger number of walnuts on a tree can result in smaller individual nuts.

A Practical Comparison of Walnut Weights

This table provides average estimates for comparing in-shell and shelled walnut weights, although actual weights can vary.


Measurement	Average In-shell Weight	Average Shelled Kernel Weight	Notes
Weight per single walnut	~11.7 g	~5.2 g (45% of in-shell)	Assumes an average 45% kernel-to-shell ratio.
Weight of 10 walnuts	~117 g	~52 g	Based on the individual average.
1-ounce serving (28g)	N/A	~5-6 kernels (~12-14 halves)	A common nutritional measure.

The Nutritional Context of Walnut Weight

Walnut weight is relevant for nutrition and portion control. Shelled walnuts are calorie-dense and rich in nutrients. A one-ounce (28-30 gram) serving of shelled walnuts, which contains about 185 calories, aligns with 5-6 kernels (each weighing around 5 grams). This serving provides significant amounts of healthy fats, antioxidants, and minerals. Knowing the average weight per nut helps in managing portion sizes for dietary goals. For additional nutrition information, refer to resources like the California Walnut Commission [https://walnuts.org/].

Conclusion: The Variability and Value of Walnut Weight

In summary, while the average in-shell walnut weighs approximately 11.7 grams, this is an estimate influenced by variety, moisture, and growing conditions. It is crucial to distinguish between in-shell and shelled weights, as the edible kernel is less than half the total weight. Using a standard serving size of about 28 grams of shelled kernels is a convenient approach for incorporating walnuts into your diet and benefiting from their nutritional value.

Frequently Asked Questions

A shelled walnut kernel typically weighs between 4 and 6 grams. This is because the kernel represents only about 40-50% of the total weight of an in-shell walnut.

The weight of a walnut can vary due to a number of factors, including the specific variety, the nut's moisture content, and the conditions under which it was grown, such as rainfall and soil quality.

A standard one-ounce (28-gram) serving of shelled walnuts is equivalent to approximately 5 to 6 whole kernels, or about 12 to 14 halves.

For most cooking and baking, measuring shelled walnut kernels by weight (in grams) is the most accurate method. If a recipe specifies "cups," it is best to use a scale to ensure precision.

Yes, there can be a significant difference. While English walnuts are the most common commercial type, black walnuts are a different species and can vary in size, shell thickness, and overall weight.

Yes, walnuts are considered a calorie-dense food. A standard 28-gram serving contains around 185 calories, most of which come from healthy polyunsaturated fats.

Yes, the weight can change slightly. As walnuts are dried for storage, their moisture content decreases, which also reduces their weight. Proper storage conditions are needed to maintain quality.