Mustard is a low-calorie condiment, but it is not always a zero-potassium food. A teaspoon of yellow mustard supplies roughly 7 mg of potassium, so large servings, creamy mustard sauces, or dry mustard powder can add up faster than you'd think. This mustard potassium calculator lets you estimate the potassium content of yellow mustard, Dijon, spicy brown, honey mustard, and dry mustard powder based on the amount you actually eat.
Nutrition labels usually list potassium in milligrams, but serving sizes can be confusing — teaspoons, tablespoons, grams, ounces, or cups. This tool converts your serving into grams, applies the appropriate potassium density, and shows your percentage of the 4,700 mg Daily Value. It's useful for people tracking potassium for kidney health, managing hypertension, or just building a more complete food diary.
🥄 Mustard Potassium Calculator
Estimate the potassium in your favorite mustard by choosing a serving size and type.
🍽️ Serving Size
🫙 Mustard Type
Step-by-Step Guide
Start by typing the amount of mustard you plan to eat in the amount field. Choose the matching unit from the teaspoon, tablespoon, cup, gram, or ounce options. If you are using a restaurant packet, a typical packet holds about 1 teaspoon or about 5 g of mustard. Next, select the mustard type, because Dijon, yellow, spicy brown, honey mustard, and dry powder all have slightly different potassium densities. Press Calculate Potassium to see the estimated potassium in milligrams, its share of the 4,700 mg Daily Value, and a short breakdown of the conversion. Use Reset to clear the results and return to the default one-tablespoon yellow mustard serving.
Potassium Reference Table
Values are based on typical USDA nutrient data for prepared mustards and dry mustard powder. Use them as a starting point; actual products can vary by brand and recipe.
| Mustard Type | Potassium per 100 g | Potassium per tsp | Potassium per tbsp |
|---|---|---|---|
| Yellow mustard (prepared) | 138 mg | about 7 mg | about 21 mg |
| Dijon mustard | 147 mg | about 8 mg | about 24 mg |
| Spicy brown mustard | 130 mg | about 7 mg | about 20 mg |
| Honey mustard | 85 mg | about 4 mg | about 13 mg |
| Dry mustard powder | 738 mg | about 21 mg | about 62 mg |
How the Calculation Works
The calculator follows a simple two-step conversion. First, it converts your serving to grams using standard weights: 1 tsp of prepared mustard is about 5 g, 1 tbsp is about 15 g, and 1 cup is about 240 g. Dry mustard powder is lighter, so the tool uses roughly 2.8 g per tsp and 8.4 g per tbsp. Then it multiplies the gram weight by the selected mustard's potassium density in milligrams per 100 g and divides by 100. The Daily Value percentage is calculated against 4,700 mg, the value used by the FDA for nutrition labels.
Potassium (mg) = Serving weight (g) × Potassium per 100 g ÷ 100. For example, 2 tbsp of yellow mustard = 30 g, and 30 × 138 ÷ 100 = 41.4 mg of potassium.
Worked Example: Dijon Dressing
Imagine you make a vinaigrette with 1.5 tbsp of Dijon mustard. Dijon weighs about 16 g per tbsp, so 1.5 tbsp is 24 g. With 147 mg of potassium per 100 g, the potassium contribution is 24 × 147 ÷ 100 = 35.3 mg, which is about 0.8% of the daily value. That is small, but if the same dressing is used daily and combined with higher-potassium foods, every gram counts.
Mustard in a Low-Potassium Diet
Prepared mustard is naturally very low in potassium, so it is usually acceptable on a potassium-restricted diet when portion sizes are reasonable. However, there are a few caveats. Yellow and Dijon mustard are also high in sodium, so people managing blood pressure or kidney disease should watch sodium alongside potassium. Honey mustard and sweet-flavored mustards add sugar and may have a slightly lower potassium density, but they can still contribute extra calories. Dry mustard powder is much more concentrated: a tablespoon provides roughly three times the potassium of a tablespoon of prepared yellow mustard. When you are tracking potassium, measure the actual amount you use instead of estimating from memory, especially if you tend to squeeze a generous swirl onto sandwiches.
Common Questions
Is mustard considered a high-potassium food? No. Prepared mustard is low in potassium, with roughly 7 mg per tsp. Even a tablespoon of yellow mustard only reaches about 21 mg, less than 0.5% of the daily value. Dry mustard powder, on the other hand, is more concentrated and can supply meaningful amounts if used in large spoonfuls for spice blends or rubs.
Why do nutrition labels list mustard potassium as 0 mg sometimes? Food labels are allowed to round small amounts to zero. A 1 tsp serving has under 10 mg of potassium, which can legally be shown as 0 mg. That does not mean mustard contains absolutely none, only that the amount is negligible in that serving size.
Are flavored mustards different? Yes. Honey mustard, beer mustard, and creamy mustard sauces often contain additional ingredients that change both the potassium density and the macronutrient profile. Honey mustard tends to have less potassium per 100 g because of its added sugar, while mustard seeds themselves are higher in potassium. If a brand publishes nutrition data, use that value for the best estimate. If you are tracking potassium from other foods too, the Brussels sprouts potassium calculator can help with another common side dish.
Additional Resources
For more detailed nutrient information, the USDA FoodData Central database provides laboratory-derived values for dozens of mustard products. The FDA's Daily Value pages explain how potassium is listed on Nutrition Facts labels, and the National Kidney Foundation offers guidance for people managing potassium intake. These sources are useful if you want to check a specific brand or understand how potassium fits into an overall eating pattern.
USDA FoodData Central · FDA Daily Value Guidance · National Kidney Foundation: Potassium