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Last updated: Aug 9, 2026

Firehouse Subs

Caramelized Onions

Large Sub ToppingsPopular

Firehouse Subs Caramelized Onions is carb-leaning, with about 88% of macro calories from carb. Each serving has 15 calories, 0.4g protein, 3.5g carbs, and 0.1g fat, making it a lighter restaurant option to compare with larger meals.

1 Ounces (28.4g)

Serving Size

28.4 g

Serving Weight

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Calories

Per serving

0.4 g

Protein

3.5 g

Carbs

0.1 g

Fat

Nutrition Facts

Amount per serving

Calories15 kcal

% Daily Value*

Total Fat 0.1 g0%

Saturated Fat 0 g0%

Trans Fat 0 g—

Cholesterol 0 mg0%

Sodium 155 mg7%

Total Carbohydrate 3.5 g1%

Dietary Fiber 0.5 g2%

Total Sugars 1.4 g—

Protein 0.4 g1%

Vitamin A—

Vitamin C—

Vitamin D—

Calcium—

Iron—

Potassium—

Caffeine—

* The % Daily Value tells you how much a nutrient in a serving contributes to a daily diet.

Nutrition Breakdown

kcal

Protein0.4 g (9%)

Carbs3.5 g (88%)

Fat0.1 g (3%)

Estimated calorie contribution using 4 kcal/g for protein and carbohydrates and 9 kcal/g for fat.

Meal Planning Insights

Protein density2.5/10

9% of macro calories come from protein.

Satiety index3.4/10

Estimated from protein, fiber, calories, and fat balance.

Activity estimate4 min walk

About 2 minutes of running for these calories.

Key Nutrients

Protein 0.4 g1%

Fiber 0.5 g2%

Sodium 155 mg7%

Sugars 1.4 g—

Saturated Fat 0 g0%

How we calculate these values

Diet Compatibility

High protein2.5/10 protein density from 0.4g protein and 15 calories.No

Lower carb3.5g carbs per serving.Yes

Low fat0.1g total fat per serving.Yes

High sugar1.4g total sugars per serving.No

High sodium155mg sodium per serving.No

Vegetarian source flagNo vegetarian flag is published for this item.Not flagged

Ingredients

ONIONS, MALTODEXTRIN, SALT, SUGAR, MODIFIED CORN STARCH, CORN SYRUP SOLIDS, AUTOLYZED YEAST EXTRACT, ONION JUICE, DEHYDRATED ONION, NATURAL FLAVORS, RED WINE EXTRACT (SULFITES), SAFFLOWER OIL, DISODIUM GUANYLATE, DISODIUM INOSINATE, YEAST EXTRACT, GUAR GUM,…

Similar Items in Large Sub Toppings

View all

Au Jus Bell Peppers5 kcal · 0.2 g protein Au Jus Mushrooms10 kcal · 1.2 g protein Avocado160 kcal · 2 g protein

Compare with other items

Select up to 3 items to compare calories, protein, sodium, and macros.

Quick comparisons

Caramelized Onions has 135 fewer calories than 1% Chocolate Milk and 6.6g less protein. Compare

Caramelized Onions has 75 fewer calories than 1% Milk and 6.6g less protein. Compare

1% Chocolate Milk150 kcal · 7 g protein1% Milk90 kcal · 7 g protein5-Cheese Mac & Cheese380 kcal · 17 g proteinApple Juice100 kcal · 0 g proteinAu Jus Bell Peppers5 kcal · 0.2 g proteinAu Jus Bell Peppers3 kcal · 0.1 g protein

Compare with 1% Chocolate Milk

Caramelized Onions Compared With Nearby Items

Compared with Au Jus Mushrooms, another Large Sub Toppings item at Firehouse Subs, Caramelized Onions has 5 more calories than it and 0.8g less protein than it. That makes this page useful for deciding between nearby menu choices, not just reading a raw nutrition label.

Data Source and Methodology

Nutrition values for Caramelized Onions are maintained in Nutrimetry from restaurant-published menu data and were last checked on Aug 9, 2026. Macro percentages use 4 calories per gram for protein and carbohydrates and 9 calories per gram for fat.

Read the data methodology

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