Guide text reviewed . Product facts and offers retain their own source dates.
How to compare protein bars
Compare UK protein and snack bars using the portion you eat, the published nutrition label and the exact pack you buy. Which Bar? (WhichBar) brings those records together; the comparisons do not measure taste or fullness.
1. Compare per bar and per 100g
Per-bar values describe one complete bar at its recorded weight. Per-100g values put differently sized bars on the same weight basis. Use both: a 40g bar and a 60g bar are different portions.
Illustrative calculation: 20g protein in a 60g bar equals approximately 33.3g protein per 100g (20 ÷ 60 × 100). Calculated figures inherit rounding from the source label.
2. Compare calories and protein together
Protein per 100 kcal = protein grams per bar ÷ calories per bar × 100. This compares protein concentration within a calorie allowance. It is a calculation, not a personal serving recommendation or a measure of taste.
Compare protein bars under 200 calories. The guide states its calorie and protein thresholds and excludes uncertain comparison values.
3. Read ingredients and dietary evidence
Open the exact product's ingredients, allergen statement and cited sources. A brand name or a similar flavour is not enough to identify a recipe. Missing evidence stays unknown; vegan status and allergy suitability are separate questions.
Compare bars recorded as vegan, with source links and the limits of that classification.
4. Compare the exact pack price
Cost per bar = pack price ÷ bars in the pack. Cost per 20g protein = cost per bar × 20 ÷ protein grams per bar. Compare the upfront pack spend as well as the calculated unit cost, and check delivery, stock and conditions at the seller.
Compare dated offers per 20g protein. Offers without the required currency, pack, stock and date evidence are excluded.
5. Follow the source and check date
Product pages link to the recorded evidence. Some per-100g figures are calculated from the serving weight; qualified or disputed information is identified or withheld. A guide's editorial review date does not mean that every product label or retailer offer was checked again that day.
Read our sources and methodology and retailer-link policy. Which Bar? is operated by Vaperama Ltd. These are label comparisons, not independent taste tests.
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