Nutrition labels list sugar and fiber per serving, but serving sizes vary wildly — a 15 g chocolate square and a 200 g yogurt pot are not comparable at face value. This calculator converts any serving-based label into the standard per-100g values used by nutritionists, diet apps, and food databases. Enter the serving weight in grams, total sugars, and dietary fiber, and the tool instantly returns sugar per 100g, fiber per 100g, the sugar-to-fiber ratio, and the combined carbohydrate contribution of these two nutrients.
Per-100g numbers make it easy to compare apples with granola bars, yogurt with dessert, and breakfast cereals with oats. This is especially useful for low-sugar eating, higher-fiber meal planning, blood sugar management, label reading, and everyday healthy eating.
🧮 Sugar & Fiber per 100g
Enter a serving size and its label values to standardize the food to a 100 g base.
Why Per-100g Values Matter
Nutrition labels list sugar and fiber per serving, but a serving can be 15 g for chocolate, 40 g for cereal, or 200 g for yogurt. Comparing those raw numbers is misleading. Converting each food to a 100 g base turns grams into a concentration that can be compared across any food. A 40 g granola bar with 8 g sugar and a 170 g yogurt with 8 g sugar look identical on labels, but the granola bar supplies about 20 g sugar per 100 g while the yogurt supplies about 4.7 g per 100 g. Per-100g values appear throughout food databases, nutrition research, package claims, and many European labels, and so they are the common language for comparing products.
This tool helps home cooks, shoppers, and diet-trackers see whether a food is mainly sugar, mainly fiber, or reasonably balanced. It is especially useful when comparing breakfast options, snack bars, fruit, canned goods, and desserts. For another high-fiber comparison, you can also use the avocado fiber per 100g calculator.
How to Use This Calculator
- Check the nutrition label for the serving size in grams. If you are working with a fresh food or recipe, weigh the amount you plan to eat.
- Enter that serving weight into the first field.
- Enter total sugars for that exact amount in grams.
- Enter dietary fiber for that exact amount in grams. If the label shows 0 g, type 0.
- Press Calculate per 100g and read the standardized results.
Use the quick-fill buttons to load examples, then edit the numbers to match your own food. The result grid shows sugar per 100g, fiber per 100g, the sugar-to-fiber ratio, and the combined weight of sugar plus fiber per 100g. The box below the grid gives a practical interpretation.
The Math Behind It
The calculation is simple scaling:
Sugar per 100g = (sugar per serving ÷ serving weight in grams) × 100Fiber per 100g = (fiber per serving ÷ serving weight in grams) × 100
Because grams per 100g is equivalent to a percentage by weight, the sugar result also tells you what percentage of the food is sugar. The sugar-to-fiber ratio is obtained by dividing the two per-100g values. A ratio below 1 means fiber is at least as abundant as sugar; a ratio above 5 means sugar strongly dominates. The combined sugar plus fiber output is not total carbs, because many foods also contain starch and other carbohydrates; it simply sums the two nutrients this calculator focuses on.
Worked Examples
Example 1: Plain Greek yogurt. Serving 170 g, sugars 4.5 g, fiber 0 g. Sugar per 100g = (4.5 ÷ 170) × 100 = 2.65 g. Fiber per 100g = 0 g. The ratio is undefined because there is no fiber. Verdict: a low-sugar dairy choice, but it is not a fiber source.
Example 2: Canned chickpeas. Serving 120 g, sugars 7.2 g, fiber 8.4 g. Sugar per 100g = 6.0 g; fiber per 100g = 7.0 g. Ratio = 6.0 ÷ 7.0 = 0.86 : 1. Here fiber actually outranks sugar, making chickpeas a strong choice for high-fiber eating.
Example 3: Chocolate caramel bar. Serving 45 g, sugars 24 g, fiber 2 g. Sugar per 100g = 53.3 g; fiber per 100g = 4.4 g. Ratio = 53.3 ÷ 4.4 = 12.1 : 1. This is a concentrated sugar source, so it makes sense to keep the portion small.
Reference Values for Common Foods
The table shows approximate values from USDA FoodData Central. Individual brands and varieties vary.
| Food | Sugars (g per 100g) | Fiber (g per 100g) |
|---|---|---|
| Apple with skin, raw | 10.4 | 2.4 |
| Banana, raw | 12.2 | 2.6 |
| Chickpeas, boiled | 4.8 | 7.6 |
| Rolled oats, dry | 1.0 | 10.6 |
| Plain low-fat yogurt | 7.7 | 0.0 |
| Cola | 10.6 | 0.0 |
Frequently Asked Questions
Does a high sugar-to-fiber ratio automatically mean a food is unhealthy? No. A strawberry has more sugar than fiber and a relatively high ratio, but it is still a nutrient-dense food. Use the ratio to identify concentrated sweets or foods where sugar clearly overshadows fiber, not to judge a single food in isolation from the rest of your diet.
Is per 100g the same as a percentage? For weight, yes. If a food contains 5 g of sugar per 100 g, then sugar makes up 5% of that food by weight. This works for nearly all foods and beverages, though it does not account for volume or density.
How is this different from net carbs? Net carbs usually means total carbohydrates minus fiber. This calculator only standardizes sugar and fiber; it does not estimate starch or total carbohydrates. For a food-specific net carb example, see the onion net carbs calculator.
What if the label already shows per-100g values? Then you can read the answer directly. This calculator is mainly useful for US-style labels that only show per-serving values. In the European Union and UK, per-100g columns are already mandatory. The FDA also explains how to interpret serving sizes on the Nutrition Facts label.