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LINE VS LINE · NULO KIBBLE

Nulo Frontrunner vs Nulo Challenger

Nulo Frontrunner vs Nulo Challenger: a bag from each line with their average protein, fat, starch and calories

Nulo Frontrunner against Nulo Challenger, measured across 6 and 5 kibble recipes: 27.0% vs 34.4% protein and 37% vs 28% starch, as fed.

6 kibble recipes reviewed 5 kibble recipes reviewed
THE SHORT VERSION

Main Differences

  • Nulo Frontrunner's recipes are all 27% protein as fed. Nulo Challenger averages 34.4% protein as fed, ranging from 32% to 35% across its recipes.
  • Nulo Frontrunner holds at 16% fat as fed. Nulo Challenger averages 17.2% fat as fed, ranging from 14% to 18%, close to Nulo Frontrunner.
  • Nulo Frontrunner's estimated starch averages 37% as fed. Nulo Challenger's estimated starch averages 28% as fed, lower across its recipes.
  • Nulo Frontrunner's 6 recipes average 431 kcal per cup, close to Nulo Challenger's 5 recipes at 425 kcal per cup; both lines show 0% grain-free share. Frontrunner's estimated price per pound is $2.82 versus Challenger's $4.42.
  • Nulo Frontrunner covers Puppy and Adult life stages for All Breeds and Small Breed dogs. Nulo Challenger has one Puppy recipe, with recipes for All Breeds, Large Breed and Small Breed dogs.
HEAD TO HEAD

The Two Lines in Figures

Measure Nulo Frontrunner Nulo Challenger Average kibble
Kibble recipes compared 6 5 1,747 in total
Protein, as fed 27.0%27.0% to 27.0% 34.4%32.0% to 35.0% 27.2%
Fat, as fed 16.0%16.0% to 16.0% 17.2%14.0% to 18.0% 14.3%
Starch, as fedEstimated, not measured. It is what is left of the guaranteed analysis once protein, fat, fiber and moisture are taken out, with ash assumed at 6%. That leftover is mostly starch but also carries sugars and the fiber a crude-fiber test misses, so read it as a close estimate rather than an exact figure. Measured as fed, the same basis as the bag. 37%37% to 37% 28%27% to 33% 37%
Calories per cup 431429 to 433 425410 to 438 398
Grain-free recipes 0% 0%
Life stages Puppy 1, Adult 1 Puppy 1
Breed sizes All Breeds 5, Small Breed 1 All Breeds 3, Large Breed 1, Small Breed 1
Price per pound, estimate $2.82/lbEstimate, median of 6 of 6 recipesRecipes run $2.61 to $2.86Prices checked Sep 28, 2026 to Oct 6, 2026 $4.42/lbEstimate, median of 5 of 5 recipesRecipes run $4.42 to $5.00Prices checked Sep 28, 2026
FDA recalls, last 5 years None None

Line figures are averages over every kibble recipe we review from that line, with the lowest and highest recipe underneath. Wet food, toppers and prescription diets are left out so the numbers compare like with like. Everything is as fed, the way the bag prints it; the switch above the table shows protein and fat on a dry matter basis instead. Why we use as fed. The price per pound is an estimate: the median of each recipe's lowest price per pound across the bag sizes and US retailers our price checks found, so a single bag can cost more or less. Shelf prices change often.

WHERE TO START

Top Recipes in Each Line

Nulo Frontrunner

Nulo Frontrunner Ancient Grains Pork, Barley & Beef Recipe Dry Dog Food Most protein in the line, 27.0% as fed Nulo Frontrunner Ancient Grains Pork, Barley & Beef Recipe Dry Dog Food Protein 27% Fat 16% Starch 37% 429 kcal/cup Nulo Frontrunner Puppy Ancient Grains Chicken, Oats & Turkey Recipe Dry Dog Food Least starch in the line, about 37% Nulo Frontrunner Puppy Ancient Grains Chicken, Oats & Turkey Recipe Dry Dog Food Protein 27% Fat 16% Starch 37% 431 kcal/cup Nulo Frontrunner Small Breed Ancient Grains Turkey, Whitefish & Quinoa Recipe Dry Dog Food Fewest calories in the line, 432 kcal per cup Nulo Frontrunner Small Breed Ancient Grains Turkey, Whitefish & Quinoa Recipe Dry Dog Food Protein 27% Fat 16% Starch 37% 432 kcal/cup

Nulo Challenger

Nulo Challenger Organic Ancient Grains Haddock, Salmon & Acadian Redfish Recipe Dry Dog Food Most protein in the line, 35.0% as fed Nulo Challenger Organic Ancient Grains Haddock, Salmon & Acadian Redfish Recipe Dry Dog Food Protein 35% Fat 18% Starch 27% 427 kcal/cup Nulo Challenger Small Breed Organic Ancient Grains Haddock, Salmon & Acadian Redfish Recipe Dry Dog Food Least starch in the line, about 27% Nulo Challenger Small Breed Organic Ancient Grains Haddock, Salmon & Acadian Redfish Recipe Dry Dog Food Protein 35% Fat 18% Starch 27% 427 kcal/cup Nulo Challenger Organic Ancient Grains Duck, Turkey & Guinea Fowl Recipe Dry Dog Food Fewest calories in the line, 423 kcal per cup Nulo Challenger Organic Ancient Grains Duck, Turkey & Guinea Fowl Recipe Dry Dog Food Protein 35% Fat 18% Starch 27% 423 kcal/cup
CHOOSING

Who Each Line Suits

A GOOD FIT FOR

Nulo Frontrunner

  • Owners seeking an Adult-stage recipe, like Nulo Frontrunner's Beef, Barley & Lamb formula.
  • Small Breed dog owners, via Nulo Frontrunner's Small Breed Turkey, Whitefish & Quinoa recipe.
  • Puppy owners of any breed size, via Nulo Frontrunner's recipe made for All Breeds puppies.
A GOOD FIT FOR

Nulo Challenger

  • Large Breed puppy owners, via Nulo Challenger's recipe made for Large Breed Puppies.
  • Owners wanting higher protein kibble, since Nulo Challenger averages 34.4% protein versus Frontrunner's 27%.
  • Small Breed dog owners, via Nulo Challenger's Small Breed Haddock, Salmon & Acadian Redfish recipe.
THE WHOLE RANGE

Every Nulo Line

Line Kibble recipes Protein Fat Starch Kcal / cup Grain-free Price / lb, est.
MedalSeries 25 30.2% 15.5% 34% 425 84% $3.37
FreeStyle 15 30.6% 15.8% 33% 406 100% $3.57
Frontrunner 6 27.0% 16.0% 37% 431 0% $2.82
Challenger 5 34.4% 17.2% 28% 425 0% $4.42
Culinary Harvest 5 30.0% 15.0% 35% 423 0% Not available
Nulo 5 30.0% 15.8% 33% 407 0% $4.35

Averages over each line's kibble we review, as fed. Lines with only a few recipes swing more on one bag. Price per pound is the same estimate as above.

KEEP COMPARING

More Nulo Line Comparisons

Nulo MedalSeries vs Nulo FreeStyle Nulo MedalSeries vs Nulo Frontrunner Nulo MedalSeries vs Nulo Challenger Nulo FreeStyle vs Nulo Frontrunner Nulo FreeStyle vs Nulo Challenger

The Nulo Lines

All Nulo food Nulo MedalSeries Nulo FreeStyle Nulo Frontrunner Nulo Challenger Nulo Culinary Harvest Nulo Nulo

Nulo Against Other Brands

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How we compare: every figure comes from the guaranteed analysis and ingredient list of recipes we review, not from the brand's own claims. Starch is our estimate, since no manufacturer prints it. The written comparison is drafted from these figures, and every number in it is checked against them. Figures refreshed October 25, 2026.

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