Nutrition labels list fat per serving, but serving sizes vary wildly between sauces and dressings. This makes it hard to compare a 15 g mayo serving with a 30 g ranch serving. The Sauce Fat Per 100g Calculator solves that by converting any sauce label into a standard per-100g figure — the same basis used by food databases and nutrition apps.
Simply enter the fat grams from one serving, the serving size, and optionally the portion you actually plan to use. The tool calculates fat per 100 g, fat per ounce, and the fat in your portion. It works for mayonnaise, salad dressings, marinades, pesto, gravy, hollandaise, hot sauce, and any other liquid or semi-liquid condiment.
Whether you’re tracking macros, comparing labels at the grocery store, or portioning sauces for a meal plan, this calculator gives you a clear, apples-to-apples number in seconds.
Turn any sauce label into a standard per-100g fat value.
How to Use This Tool
Start by reading the Nutrition Facts panel on your sauce bottle. The two numbers you need are Total Fat per serving (in grams) and Serving Size. Most sauce labels list serving size in grams for thicker products like mayonnaise and pesto; thinner dressings are sometimes listed in milliliters or tablespoons. If the label gives a volume unit, convert it to grams using the product density. As a rough guide, 1 tablespoon of most creamy dressings weighs around 15 grams, and 1 fluid ounce of a typical dressing weighs about 28–30 grams. For the most accurate result, weigh your serving on a kitchen scale.
Enter the fat value and serving size, then select whether the serving size is in grams or ounces. If you know how much sauce you'll actually eat, enter that portion weight in the optional field. The calculator will show:
- Fat per 100 grams — the standardized number for comparing products.
- Fat per 1 ounce — useful when a recipe calls for ounces.
- Fat in your portion — the number that matters for your meal.
The Calculation Formula
The calculator uses a simple proportion:
Fat per 100 g = (Fat per serving ÷ Serving size in grams) × 100
For example, if a label says 11 g of fat per 15 g serving, then fat per 100 g is (11 ÷ 15) × 100 = 73.3 g. If the serving size is in ounces, the calculator first converts it to grams by multiplying by 28.3495, then applies the same formula.
This standardization matters because it removes serving-size bias. A product's "per serving" number can look small simply because the serving size is tiny, while a product with a larger serving size can look higher in fat even though it's actually leaner per gram. Per-100g values put every sauce on the same scale.
Worked Examples
Example 1 — Mayonnaise label. A mayonnaise label shows Total Fat 12 g per serving, serving size 15 g. Using the calculator: (12 ÷ 15) × 100 = 80 g fat per 100 g. If you use 20 g of mayo, your portion contains (12 × 20) ÷ 15 = 16 g of fat.
Example 2 — Bottled vinaigrette. A balsamic vinaigrette label says 7 g fat per serving, serving size 1 oz. The calculator converts 1 oz to 28.35 g, giving (7 ÷ 28.35) × 100 ≈ 24.7 g per 100 g. A 45 g salad portion of dressing has about (7 × 45) ÷ 28.35 ≈ 11.1 g of fat.
Notice how different the per-100g numbers are: mayo at 80 g per 100 g is a very high-fat food, while vinaigrette at 24.7 g per 100 g is moderate. This is the core value of standardizing.
Sauce Fat Reference
These approximate ranges come from USDA FoodData Central and typical grocery-store labels. Always check the label on your specific product, because recipes vary widely between brands.
| Sauce / Condiment | Typical fat per 100 g |
|---|---|
| Mayonnaise | 75–80 g |
| Hollandaise | 55–70 g |
| Caesar dressing | 50–60 g |
| Pesto | 40–60 g |
| Ranch dressing | 35–50 g |
| Blue cheese dressing | 30–45 g |
| Balsamic vinaigrette | 20–35 g |
| Soy sauce | 0–1 g |
| Hot sauce | 0–1 g |
| BBQ sauce | 0–3 g |
| Marinara | 1–4 g |
For precise values, search the exact product in USDA FoodData Central at fdc.nal.usda.gov.
Common Mistakes to Avoid
Forgetting to convert ounces. If you enter 1 oz as "1 g", every result will be inflated by 28×. Always check the unit selector.
Using volume for dense sauces. A tablespoon of creamy dressing and a tablespoon of vinaigrette have different weights. Weigh in grams whenever possible.
Assuming same type = same fat. Light mayo can have half the fat of full-fat mayo, and organic brands often change oil blends. Use your actual label.
Skipping the portion field. Fat per 100 g is great for comparison, but your actual fat intake depends on how much sauce you plate. If you tend to double the serving size, enter your real portion to see the difference.
Why Per 100g Is Useful
Nutrition apps and food databases generally report nutrients per 100 g, so standardizing your condiments lets you log them accurately. It also lets you make direct comparisons: a 5 g fat-per-serving claim means nothing unless you know the serving size. Once both sauces are expressed per 100 g, the higher-fat option is obvious.
This same approach applies to other calorie-dense foods, spreads, and dressings. If you're tracking overall energy intake, pair this tool with a fat loss calorie calculator to see how sauce fat fits into your daily calorie goal. For another high-fat pantry item, you can also standardize jam fat per 100g to compare breakfast spreads.
Per-100g values are the universal language of food labels and nutrition research. Making it a habit to mentally convert — or quickly calculating it here — turns confusing label numbers into practical meal-planning facts.