← All posts

    Best Protein Bars: 15 Ranked by Ingredients

    By Guiltless ·

    There is no single best protein bar, but there is a fair way to compare them: grams of protein per 100 calories, then what makes the bar sweet and where its protein comes from. Of 15 popular protein bars compared by their US labels, the David Protein Bar came first at 18.7 g of protein per 100 calories and KIND Protein last at 4.8 g.

    If you compare bars in the store, Guiltless, the grocery app we make, lets you filter products by protein and see their ingredient lists.

    How we ranked the bars

    We put 15 protein bars in order of grams of protein per 100 calories, using one popular flavor of each and its US label.

    People buy protein bars for protein, and this number shows how much of it you get for the energy in the bar. It also works across bar sizes. Our bars weigh from 40 g to 71 g, so "per bar" alone can mislead. For comparing two bars by weight instead, see how to compare two snack bars. You can also calculate it while you shop: a bar with 20 g of protein and 200 calories has 20 ÷ 200 × 100 = 10 g of protein per 100 calories.

    The ranking also has limits.

    • It is one number, not a judgment of how healthy a bar is. It says nothing about taste, price, protein quality, sweeteners or allergens.
    • Labels round. Calories are rounded to the nearest 10 and protein to the nearest gram, so bars within about 1 g of protein per 100 calories of each other could change places in the ranking.
    • Recipes change. Some retailer listings showed older recipes for several of these bars, so check the wrapper you buy.

    The 15 bars, ranked by protein per 100 calories

    Rank Bar and flavor (US) Protein, calories Protein per 100 cal Added sugars Sugar alcohols
    1 David Protein Bar, Chocolate Chip Cookie Dough 28 g, 150 18.7 g 0 g 7 g
    2 Built Puff, Coconut 17 g, 140 12.1 g 6 g None listed
    3 (tie) Kirkland Signature Protein Bar, Chocolate Chip Cookie Dough 21 g, 190 11.1 g 2 g 2 g
    3 (tie) Quest Protein Bar, Chocolate Chip Cookie Dough 21 g, 190 11.1 g 0 g 6 g
    5 (tie) Barebells Protein Bar, Cookies & Cream 20 g, 200 10.0 g 0 g 5 g
    5 (tie) Pure Protein Bar, Chocolate Peanut Butter 20 g, 200 10.0 g 1 g 6 g
    7 No Cow Protein Bar, Chocolate Fudge Brownie 20 g, 210 9.5 g 0 g 6 g
    8 ONE Protein Bar, Birthday Cake 20 g, 220 9.1 g 0 g 7 g
    9 SimplyProtein Crispy Bar, Mint Chocolate Chip 13 g, 150 8.7 g 2 g None listed
    10 think! High Protein Bar, Brownie Crunch 20 g, 240 8.3 g 0 g 11 g
    11 Clif Builders, Chocolatey Peanut Butter 20 g, 290 6.9 g 17 g None listed
    12 RXBAR, Chocolate Sea Salt 12 g, 200 6.0 g 0 g None listed
    13 ALOHA Protein Bar, Chocolate Chip Cookie Dough 14 g, 240 5.8 g 4 g None listed
    14 Perfect Bar, Peanut Butter 17 g, 340 5.0 g 13 g None listed
    15 KIND Protein, Crunchy Peanut Butter 12 g, 250 4.8 g 5 g None listed

    US labels, one flavor per bar. Protein per 100 calories is calculated from the label. Perfect Bar is sold refrigerated. Other flavors of the same bar can have different labels.

    Bar chart of 15 protein bars ranked by grams of protein per 100 calories: David 18.7, Built Puff 12.1, Kirkland Signature and Quest 11.1, Barebells and Pure Protein 10.0, No Cow 9.5, ONE 9.1, SimplyProtein Crispy 8.7, think! 8.3, Clif Builders 6.9, RXBAR 6.0, ALOHA 5.8, Perfect Bar 5.0, KIND Protein 4.8.
    Protein per 100 calories, from each bar's US label.

    The best protein bar for your goal

    Pick the goal first, then the bar. Every pick here comes with a trade-off.

    • Most protein for the calories among the 15: David. 28 g of protein in 150 calories. It uses maltitol (7 g of sugar alcohols), allulose, sucralose and acesulfame potassium, and its protein blend includes collagen.
    • High protein for the calories, without sugar alcohols: Built Puff. 17 g of protein in 140 calories, sweetened with sugar (6 g added sugars). Its protein is whey protein isolate with collagen and gelatin.
    • No added sugars and no sugar substitutes: RXBAR. Sweetened with dates, so it has 0 g added sugars but 14 g of total sugars. Its 12 g of protein comes from egg whites and nuts.
    • Plant protein without soy: No Cow or ALOHA. No Cow has 20 g of protein from brown rice and pea protein, with erythritol and stevia, and 15 g of fiber. ALOHA has 14 g from brown rice and pumpkin seed protein, sweetened with syrups and sugar (4 g added sugars). ALOHA's ingredients include none of the major food allergens, so its label has no "Contains" line; it says it is made in a facility that also processes tree nuts, peanuts, milk, soy, wheat, fish and sesame. Clif Builders and SimplyProtein are plant-based too, with soy protein.
    • Most protein of the 15 without a sugar substitute: Clif Builders. 20 g of protein from soy, sweetened with cane syrup, cane sugar and brown rice syrup, which add up to 17 g of added sugars in 290 calories.
    • A bar that is more like a small meal: Perfect Bar. Peanut butter is its first ingredient, followed by honey. At 71 g and 340 calories, with 17 g of protein and 13 g of added sugars, it is the largest bar here.

    If you have a food allergy, read the Contains line on the wrapper you buy. 10 of the 15 have peanuts or tree nuts in their ingredients, and the other 5 have a "may contain" or shared-facility statement that names peanuts or tree nuts. Guiltless also has allergen filters, including peanut and nut, when supported. The same advice applies: check the label.

    Why a protein bar can say "0 g sugar" and still taste sweet

    A bar with 0 g of sugar is usually sweetened with sugar alcohols, allulose or a high-intensity sweetener, none of which count as sugars on a US label.

    Diagram grouping the 15 protein bars by what sweetens them. Dates only: RXBAR. Sugars, syrups or honey: Built Puff, SimplyProtein, ALOHA, KIND Protein, Perfect Bar, Clif Builders. Sugar alcohols with or without other sweeteners: Kirkland Signature, Quest, Barebells, Pure Protein, No Cow, ONE, think!. Sugar alcohols plus allulose: David.
    What sweetens each bar, from its US ingredient list.

    Sugar alcohols, allulose and high-intensity sweeteners are each treated differently from sugar, on the label or by regulators.

    • Sugar alcohols (names often end in "-itol," like maltitol and erythritol) aren't counted in Total Sugars or Added Sugars. Listing them is voluntary unless the label makes a claim about sugar or sugar alcohols. The FDA counts maltitol at 2.1 calories per gram and erythritol at 0, compared with 4 for sugar.
    • Allulose is a sugar the FDA allows manufacturers to exclude from Total Sugars and Added Sugars under its 2020 guidance, counted at 0.4 calories per gram. It still counts in Total Carbohydrate. David lists allulose without an amount.
    • High-intensity sweeteners such as sucralose, stevia and acesulfame potassium are used in tiny amounts. 5 of our bars list sucralose. The FDA has approved sucralose and acesulfame potassium as food additives, and has not objected to makers' conclusions that highly purified stevia extracts are generally recognized as safe. The 2025-2030 Dietary Guidelines for Americans advise limiting foods with low-calorie non-nutritive sweeteners, and name sucralose and acesulfame potassium among the examples.

    Can sugar alcohols cause stomach problems?

    Sugar alcohols can cause gas, bloating or diarrhea in some people, the FDA says. The type of sugar alcohol and the amount eaten matter.

    • Erythritol: in a 2007 randomized trial of 64 young adults, 20 g and 35 g, taken once in a drink, were "tolerated well, without any symptoms." At 50 g, nausea and stomach rumbling increased.
    • Maltitol: in a 2003 trial of 12 healthy adults who took increasing amounts through the day, diarrhea appeared only at very high doses, around 92 g a day. In a 2014 trial of 32 adults, desserts with 35 g of sweetener mixes containing maltitol, a fiber (short-chain fructo-oligosaccharides) or both caused mild, short-lived symptoms.
    • Added fibers: chicory root fiber (inulin) is in KIND Protein, Clif Builders and SimplyProtein. In a 2010 trial of 26 adults, up to 10 g a day of chicory inulin was well tolerated, and the most common symptoms were gas and bloating.

    The bars here list 2 g to 11 g of sugar alcohols each, less than the doses in those studies, but the studies were small and mostly tested single doses, and people differ. If you're trying a new bar, eat one bar first and see how you feel.

    What "net carbs" means

    "Net carbs" has no FDA definition. Brands that print it usually subtract fiber and sugar alcohols from Total Carbohydrate, each in their own way. On a US Nutrition Facts panel, Total Carbohydrate includes fiber, sugar alcohols and allulose, so it is the number to compare between bars.

    Where the protein in a protein bar comes from

    Ingredients are listed in order from most to least by weight, so the first protein ingredient is a good clue to where most of the protein comes from. In our 15 bars:

    • Milk proteins (milk protein isolate, whey, casein): first in David, Built Puff, Kirkland Signature, Quest, Barebells, Pure Protein and ONE, and part of the blend in the think! bar.
    • Soy protein: first in Clif Builders, SimplyProtein and think!, and part of the blend in Barebells, Pure Protein and KIND Protein.
    • Egg whites: RXBAR, and part of David's blend.
    • Nuts and peanut butter: first in KIND Protein (peanuts) and Perfect Bar (peanut butter).
    • Plant blends: brown rice and pea in No Cow, brown rice and pumpkin seed in ALOHA.
    • Collagen or gelatin: David, Built Puff, Barebells and Pure Protein.

    Collagen is the protein source to know about. It lacks tryptophan, so, in theory, collagen on its own rates zero on the standard protein quality score, as a 2019 calculation study in Nutrients noted. The same study found collagen could supply up to 36% of the protein in a typical US diet while amino acid needs are still met. Collagen still counts in a label's grams of protein.

    When a US label shows a %Daily Value for protein (required when it makes a protein claim), the FDA requires that figure to be corrected for protein quality, whatever the protein source, so it can be lower than the grams suggest. For example, KIND Protein, which has no collagen, lists 12 g at 14% DV, while 12 g would be 24% of the 50 g Daily Value without the correction.

    How much protein should a bar have?

    That depends on how much protein you need in a day, not on the bar. The National Academies set the Recommended Dietary Allowance at 0.8 g of protein per kg of body weight a day. The 2025-2030 Dietary Guidelines for Americans set a higher goal of 1.2 to 1.6 g per kg.

    For someone who weighs 70 kg (154 lb), that comes to 56 g a day at the Recommended Dietary Allowance and 84 to 112 g a day at the Dietary Guidelines goal. A 20 g bar covers about a third of 56 g, or about a fifth of 100 g, which is near the middle of the 84 to 112 g range. If you have kidney disease or another condition that changes your protein needs, ask your doctor or a registered dietitian.

    Five checks before you buy a protein bar

    Before you buy a bar, read five things on the wrapper. Calculate its protein per 100 calories: grams of protein divided by calories, times 100. Check where the protein comes from, since collagen counts in the grams but lacks tryptophan. See what makes it sweet: the Added Sugars line, then the ingredients for sugar alcohols, allulose or high-intensity sweeteners. Note the fiber source, because added fibers such as chicory root fiber (inulin) can cause gas or bloating in some people. Last, read the Contains line for allergens.

    Checklist titled '5 checks before you buy a protein bar': protein per 100 calories, where the protein comes from, what makes it sweet, the fiber source, and the Contains line.
    A checklist to save. It summarizes the sections above.

    Compare protein bars before you buy

    Calculating protein per 100 calories for every bar on a shelf takes a while. Guiltless can first narrow down the products you need to check. It doesn't calculate protein per 100 calories, so you still need to do that math yourself. In Guiltless, you can:

    • set a protein range with the macro (macronutrient) filter, which also covers carbs and fat, and set a calorie range
    • filter by diet type, such as High Protein or Low Sugar, when supported
    • scan a barcode or search for a product to see its ingredient list, Nutrition Facts and its GCR Score (Guiltless Certified Rating), a 0 to 100 rating that considers nutrition, ingredients, additives and processing together

    Filter results depend on the product data, so check the wrapper too. You can scan barcodes, though not every product is in the app.

    Guiltless filter screen showing a Protein (g) range slider set from 0 g to 100 g, with minimum and maximum boxes.
    1. Set a protein range in grams.
    Guiltless Diet Type filter list showing Pescetarian, Paleo-Friendly, High Protein, Low-Fat and Low Sugar, each with a checkbox.
    2. Or filter by diet type, such as High Protein.
    Ingredients tab of a scanned product in Guiltless (in this example, a bagel), listing modified wheat starch, wheat gluten, a sweetener blend of erythritol and stevia, wheat protein and other ingredients.
    3. Open a product to read its full ingredient list. This example is a bagel.Guiltless and the GCR Score provide general informational guidance and are not medical advice. Individual nutrition needs vary. Users with medical conditions, allergies or specific dietary requirements should consult an appropriate qualified professional and review product labels.

    In the third screenshot, a sweetener blend of erythritol and stevia appears near the top of the ingredient list. The Sugars line alone wouldn't tell you that.

    Try the Guiltless App

    FAQ

    Are protein bars healthy?

    It depends on the bar and on what it replaces. The 15 we compared ranged from 4.8 g to 18.7 g of protein per 100 calories and from 0 g to 17 g of added sugars, so "protein bar" covers very different foods. Compare protein per 100 calories, the sweeteners and the protein source.

    Which protein bars have no sugar alcohols?

    Of the 15 we compared, RXBAR, Built Puff, SimplyProtein Crispy, Clif Builders, ALOHA, Perfect Bar and KIND Protein have no sugar alcohols in their ingredients (KIND Protein's label shows 0 g). Four of these 7 (Built Puff, SimplyProtein Crispy, Clif Builders and ALOHA) list glycerin as an ingredient, and SimplyProtein's label shows 2 g of it.

    Why do protein bars give me gas?

    Sugar alcohols and added fibers such as inulin (chicory root fiber) can cause gas or bloating in some people. In one trial, erythritol in a drink caused no significant symptoms at 20 or 35 g, and in another, up to 10 g a day of inulin was well tolerated, and gas and bloating were the most common complaints. People's tolerance varies.

    What does "net carbs" mean on a protein bar?

    "Net carbs" has no FDA definition. Brands usually subtract fiber and sugar alcohols from Total Carbohydrate, each in their own way. Compare Total Carbohydrate on the Nutrition Facts panel instead.

    How much protein should a protein bar have?

    There's no official number for a bar. The bars we compared had 12 g to 28 g. What matters is your day's total: the National Academies' Recommended Dietary Allowance is 0.8 g per kg of body weight a day, and the 2025-2030 Dietary Guidelines for Americans set a goal of 1.2 to 1.6 g per kg.

    Is it OK to eat a protein bar every day?

    A protein bar can be part of what you eat in a day, but bars differ a lot in added sugars, sweeteners and calories. If you eat one daily, check those lines, and see how you feel with sugar alcohols and added fibers.

    This article is general information, not medical advice. If you have a health condition, a food allergy or specific nutrition needs, talk to a doctor or registered dietitian.

    Sources

    Product labels: US labels from each brand's website, read on October 8, 2026, except RXBAR's, read on Kellanova's SmartLabel (last updated May 6, 2024; it matched Target's listing on October 8, 2026). On that date, some retailer listings showed older recipes for several of the bars. Other sources were read on October 8, 2026.

    Related posts