A little clarity at the shelf
Two labels.
A clearer comparison.
Put two similar foods on the same footing. Compare the numbers per 100g, then see what changes for the portions you choose.
Start with the back of the pack
Copy the per 100g column for both foods, using kcal for energy and grams for nutrients. Compare both as sold, or both prepared the same way. This tool does not compare drinks or convert per-100ml labels.
Fictional example: these numbers teach the comparison and do not represent products you can buy.
Leave unavailable values blank; blank does not mean zero. Enter at least one matching nutrient or energy value for both foods. Use exact numbers, not “<0.1”.
Add a portion weight for each food to see a separate portion comparison. This is the amount you choose, not a recommended serving.
Your comparison
The numbers, side by side.
These are arithmetic comparisons of the values you entered. Differences alone do not decide which food fits your diet. Values are rounded to two decimal places.
Saving stores this comparison only in this browser. Anyone using the same browser may be able to restore it. Clearing browser data removes it.
Read the whole label
The useful bit
behind the numbers.
Why use the same 100g basis?
Different pack sizes and suggested servings can make a side-by-side glance misleading. The same weight gives you one consistent starting point. A portion calculation then answers a different question: what is in the amount you plan to eat?
What do these words mean?
Saturates means saturated fat and is part of the total fat figure. Total sugars includes sugars naturally present in the food as well as added sugars; it does not identify added sugar by itself. Enter the label’s salt value, not sodium. Energy here uses kcal, not kJ.
What if one value is missing?
Leave it blank. The result keeps it as “Not entered” and does not calculate a difference for that row. Fibre may not appear on every label. Ingredients, allergens, price and what you enjoy still matter alongside the nutrition panel.
A worked example, without the calculator
Imagine two fictional foods with 8g and 10g of fat per 100g. Food B has 2g more fat at that weight. But 30g of A contains 2.4g of fat, while 20g of B contains 2g. The portion result changes because the amounts differ, not because either label changed.
The calculation is: value per 100g × portion weight ÷ 100.
Label-reading reference: NHS: Food labels. Tool notes checked September 2026.