How we score what you scan
Every product gets scored the same way: the nutrition label, the ingredient list, and a fixed set of rules. No guesswork.
The short version
We start with adjusted net carbs in a typical serving, look at what the ingredient list says, and pay some attention to the food's macro shape (whether the calories are mostly carbs or mostly fat). Some ingredients are also a signal that the label carb count can't be taken at face value, so we adjust for that too.
All of that combines into a 0 to 100 score, which maps to Excellent, Good, Caution, or Avoid.
Verdicts
Our scoring categories on Keto Peek, and what they mean for you.
Excellent (90–100)
Fits strict keto on both the carb and ingredient side. These are foods you can eat freely without much thought.
Examples: meat, fish, eggs, non-starchy vegetables, most cheeses, butter, oils.
Good (70–89)
Works on keto, but portions matter. Large servings will add up fast, so pay attention to how much you're eating.
Examples: nuts, dark chocolate, full-fat yogurt, some packaged keto snacks, many sugar-free condiments.
Caution (40–69)
Something is off, whether that's the carb count, the ingredients, or both. It might fit as a small portion, but it's not a safe default.
Examples: some keto-labeled breads and bars, low-carb ice cream, sugar-free candy, ready-to-drink protein shakes.
Avoid (0–39)
Too many carbs for a keto diet, poor ingredients, or both. Not a portion-control situation.
Examples: regular bread, most candy, sweet drinks, desserts, breakfast cereals, most grain-based snacks.
Unknown
The label is missing key data, usually total carbs or fiber, so we can't calculate net carbs. We don't fill in gaps or guess.
What we look at
Net carbs per serving
We start with total carbs and subtract fiber and sugar alcohols when the label lists them. But we don't always take those numbers at face value. Certain ingredients are a signal that the "free" carbs may be overstated, because some fibers and sugar alcohols don't behave like zero in your body.
For a deeper look at how we handle this, see Sugar alcohols and keto.
Ingredient quality
The carb count only tells part of the story. We also look at the ingredient list for sugars (named per ingredient), other sweeteners like sucralose and aspartame, refined flours and starches, certain sugar alcohols like maltitol and IMO, top-3 seed oils, and artificial colors. These move a score down independently of the carb math.
Keto breads get their own treatment, because the labels in that category are especially easy to misread. See Keto bread and ketosis for how we approach those.
Why two foods with similar carbs can score differently
Not all carbs are created equal, and neither are the foods that contain them. A few things can shift a score even when the numbers look similar at first glance.
Serving size plays a bigger role than most people expect. We score the label as written, so two foods with identical carbs per 100g can land differently just because their serving sizes aren't the same.
Ingredient quality matters too. The same net carb count can come from very different sources, and we treat them accordingly. Eggs and nuts aren't in the same category as IMO syrup or heavy maltitol, and the score reflects that.
Macro shape matters. A food where most of the calories come from carbs (and very little from fat) gets a small extra deduction, even if its gram count looks borderline. Old-fashioned oats, white rice, sugary drinks, and pure-fruit products fall into this — they're carb-dominated by composition, which is the opposite of how a keto plate is balanced.
Going deeper
How the math actually works
Net carbs+−
The biggest chunk of the score comes from net carbs in a serving. The penalty grows smoothly as net carbs go up — the more carbs, the bigger the deduction:
- 2 g — small penalty (~5 points off)
- 5 g — ~15 points off
- 10 g — ~30 points off
- 15 g — ~50 points off
- 20 g — ~70 points off
- 30 g+ — maximum penalty (~90 points off)
Values between these anchors are interpolated on a smooth curve. A 7 g product is meaningfully different from a 9 g product, not lumped into the same bucket.
Macro shape+−
We compute what share of a food's calories come from carbs vs. fat. A food that's mostly carbs (low fat, high carb share) gets a small extra deduction — at most about 15 points, less for borderline cases. High-fat foods get a free pass even when carbs creep up; that's the keto-shaped half of the macros.
Real keto foods (butter, eggs, almonds, peanut butter, full-fat dressings) get nothing here. Old-fashioned oats, white rice, plain fruit, and sugary drinks — products where carbs dominate the calorie mix — pick up the full penalty.
The lane stays silent for very low-calorie servings (under ~30 cal), where the macro ratio isn't a meaningful signal.
Sugars+−
Caloric sugars detected in the ingredient list (cane sugar, HFCS, honey, agave, maltodextrin, brown sugar, fruit juice concentrate, and so on) each show up as their own row in the breakdown. They share a small total budget — a product with one cane-sugar entry and a product with four split sugar entries get roughly the same total penalty, but the four-sugar product makes the splitting visible to you.
The point isn't to pile on a product with one or two grams of sugar — the carb count already does that. This row says "and the carbs that arethere are coming from refined sugar specifically."
Other sweeteners+−
Non-caloric and synthetic sweeteners (sucralose, aspartame, acesulfame potassium, saccharin, etc.) get their own small budget, distributed across each one detected. Stevia, monk fruit, allulose, and other "best tier" keto sweeteners do not contribute a penalty — those are the ones we want to encourage.
Sugar alcohols are handled separately upstream in the net-carb math, not here. See Sugar alcohols and keto.
Specific ingredients we always penalize+−
A short list of ingredients gets its own dedicated deduction, on top of any sweetener or carb math. These are ingredients keto eaters specifically care about — they're harmful or misleading on a keto label regardless of how the rest of the math works out:
- Trans fats / partially hydrogenated oils
- Modified wheat starch / RS4 / Fibersym
- IMO / "soluble tapioca fiber"
- Modified food starch
- Maltitol and maltitol syrup
- Hydrogenated starch hydrolysates
- Refined flour and refined starch (when they're a top-3 ingredient)
- Inflammatory seed oils (when they're a top-3 ingredient)
- Artificial colors
How everything combines+−
Every food starts at 100 points. Each lane above contributes its own deduction. The total of every deduction is subtracted from 100, clamped at 0, and that's the final score.
There's no blend, no weighted average, no post-adjustment cap. The score reads like simple subtraction, top to bottom: max score, minus each row, equals final score.
No score is perfect+−
No label-based system is perfect, and ours is no exception. These tiers are meant to point you in the right direction, not hand down a verdict on every product for every person.
If you're agonizing over a point or two on a score, you've gone deeper than this tool was designed to go. Keto Peek is built for quick, practical decisions in the store aisle, not to produce a perfect number for its own sake.
We're not trying to be the final word on keto, and we'd encourage you not to treat any scanning app (including this one) as your only source of truth. Pay attention to how you actually feel. Watch how your energy, hunger, and cravings respond. If you use a glucose monitor, your own blood sugar data is the most honest feedback you'll get. The score is one useful input, not a replacement for listening to your body.
Still have thoughts or questions? We'd love to hear from you. Drop us a line.