How Koracle scores products
In this article
What the scoring engine does
Most skincare rankings start with popularity. Koracle starts with fit. It checks each product against your skin profile, then weighs concern match, evidence, formula confidence, texture, sensitivity, barrier state, experience level, sunscreen quality, and routine conflicts. No brand pays to be included or ranked higher.
The same formula applies to every product. An $8 cleanser and a $45 serum enter the same scoring pipeline.
Research basis
Evidence tiers
Each product's hero ingredient is assigned an evidence tier based on the depth of published research behind it. Tier assignments draw from dermatology and cosmetic chemistry references including Baumann's Cosmetic Dermatology, Bolognia's Dermatology Essentials, and Harry's Cosmeticology. The engine can also adjust evidence by concern, because an ingredient may be proven for acne but weaker for sensitivity or surface hydration.
Multiple randomized controlled trials. Examples: niacinamide, retinol, hyaluronic acid, salicylic acid, vitamin C, ceramides.
Published clinical or in-vitro studies with consistent results. Examples: centella asiatica, peptides, tea tree, green tea, alpha-arbutin, squalane.
Early research or strong mechanistic rationale but limited clinical data. Examples: snail mucin, galactomyces, PDRN, propolis.
Long history of use in Korean or East Asian skincare with minimal formal study. Examples: rice bran, ginseng, artemisia.
The formula
How scoring works
When you complete the quiz, the engine scores every catalog product against your profile. The formula turns concern fit, formula quality, and routine safety into one score per product.
Your primary concern counts 3x, secondary concern 1.5x, and tertiary concern 0.75x. Each product has pre-computed concern scores (0-10) for conditions like acne, hyperpigmentation, and dehydration. A serum with a concern score of 8 for acne and your primary concern is acne contributes 8 * 3 = 24 points.
Chronic concerns get a 1.15x multiplier (longer-term issues benefit from stronger actives). Temporary concerns get 0.95x.
Products are classified as light, medium, or heavy texture. Oily skin gets +2 for light textures and -2 for heavy ones. Dry skin is the reverse: +2 for heavy, -1 for light. This pushes gel moisturizers toward oily skin and rich creams toward dry skin.
The subtotal is multiplied by the hero ingredient's evidence tier (1.25x down to 0.95x), and some ingredients are graded by concern. BHA scores stronger for acne/pores than sensitivity. Collagen is treated as surface hydration, not dermal rebuilding.
Reviewed formulas, full INCI lists, clear sunscreen filters, and verified source data get a small lift. Key-ingredient-only, text-inferred, or low-confidence formulas are demoted until they are reviewed.
A small fraction (potency / 50) breaks ties between products that score similarly on the above factors.
See how these factors play out for your skin type and concerns.
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Additional scoring adjustments
The engine applies targeted adjustments for specific skin situations that need special handling.
Products are rated on intensity (1-10). For sensitive skin, anything above intensity 3 gets penalized: intensity 4-5 scores at 60%, intensity 6-7 at 30%, and intensity 8+ at just 10% of its base score.
Products flagged as currently unavailable on Amazon score at 30% of their normal value. They can still appear as alternatives but won't be the top pick.
Light textures (emulsions, essences) get a +3 bonus. Heavy textures (creams, occlusives) get a 0.5x penalty. Hyaluronic acid products get +2. This prevents the engine from recommending thick creams to oily skin that just needs water-binding hydration.
Acne-prone, rosacea/flushing, stinging, and contact-dermatitis profiles are handled differently. The engine checks comedogenic ingredients, vasodilating irritants, stinging triggers, fragrance, preservatives, and allergens.
Pigment-focused and high-sun profiles get extra credit for broad-spectrum, photostable, zinc oxide, and tinted/iron-oxide sunscreen signals. Unknown sunscreen filters and likely cast risks are demoted.
The engine downgrades textbook-debunked claims such as topical collagen rebuilding dermal collagen, cosmetics stopping baseline sebum production, or natural meaning automatically safe.
Within each routine step, only the top-scoring product per hero ingredient is kept. This prevents your serum slot from being filled with four different niacinamide options.
Safety rails
Experience gating
Products tagged as advanced-level (high-concentration retinol, strong chemical peels) are filtered out for beginner users. Sensitive, barrier-compromised, pregnancy/lactation, and low-tolerance profiles get stricter filtering before ranking happens. If a retinoid or acid is appropriate, the engine favors gradual introduction and barrier support rather than stacking strong actives.
Boundaries
What we don't do
Koracle is picky on purpose.
We don't test products on skin. Scores are based on ingredient research and product data, not our personal use.
We don't diagnose acne, rosacea, melasma, eczema, allergic dermatitis, or infection. Persistent, painful, severe, spreading, or rapidly changing symptoms belong with a licensed clinician.
No brand deals or sponsorships. Products enter the catalog through automated sourcing pipelines that search Korean beauty databases and Amazon listings.
No sponsored placements. There is no mechanism for a brand to pay for a higher score or preferred position.
No pay-to-rank. The scoring formula is the same for a $8 cleanser and a $45 serum.
We don't treat marketing claims as proof. Recommendations come from published ingredient research, product formulation data, formula-confidence checks, and the concern-matching algorithm described above.
Freshness
Keeping products current
Automated pipeline searches Amazon for new K-beauty products, classifies them, and validates images.
Comparison pipeline checks if new products outperform existing ones and flags potential swaps.
Checks Amazon freshness so unavailable products drop out of top picks.
Clinical citations by tier
Specific findings from dermatology textbooks that informed each ingredient's tier assignment.
Proven-tier ingredients
Niacinamide
- [Baumann, Ch. 33: Depigmenting Agents] 5% niacinamide applied twice daily for 8 weeks inhibits melanosome transfer to keratinocytes by up to 68% in vitro.
- [Baumann, Ch. 32: Moisturizing Agents] Exhibits anti-inflammatory, antioxidant, and immunomodulatory properties in addition to depigmenting effects.
Ceramides
- [Baumann, Ch. 32: Moisturizing Agents] A 3:1:1:1 ratio of ceramides, cholesterol, essential FFAs, and nonessential FFAs accelerates skin barrier recovery.
- [Baumann, Ch. 32: Moisturizing Agents] Incomplete lipid mixtures missing ceramides delayed barrier recovery and produced abnormal lamellar bodies.
Azelaic Acid
- [Baumann, Ch. 33: Depigmenting Agents] 20% azelaic acid cream produced significantly greater decreases in pigmentary intensity than vehicle in controlled trials.
- [Baumann, Ch. 33: Depigmenting Agents] More effective than hydroquinone for melasma without the latter's side effects; scavenges hydroxyl radicals.
BHA
- [Baumann, Ch. 15: Acne] Salicylic acid is one of only three agents that support already-visible blemishes, not just prevent future ones.
- [Bolognia, Ch. 29: Acne Vulgaris] Beta hydroxy acids penetrate lipid-rich follicular environments to dissolve comedonal plugs and reduce inflammation.
Hydrocolloid
- [Baumann, Ch. 32: Moisturizing Agents] Occlusive wound dressings maintain a moist environment that accelerates re-epithelialization compared to dry recovery.
Vitamin C
- [Baumann, Ch. 34: Antioxidants] The only antioxidant that can improve the look of visible wrinkles through direct stimulation of collagen formation.
- [Baumann, Ch. 34: Antioxidants] Combined 1% alpha-tocopherol + 15% L-ascorbic acid provided superior photoprotection compared to either alone.
Retinol
- [Baumann, Ch. 30: Retinoids] Tretinoin inhibits UV-induced matrix metalloproteinases that degrade collagen types I, III, and VII.
- [Baumann, Ch. 30: Retinoids] In a randomized study of 100 subjects, both 0.1% and 0.025% tretinoin improved photoaged skin vs. vehicle.
- [Baumann, Ch. 15: Acne] Tretinoin has superior ability to eradicate existing comedones and prevent new ones by normalizing keratinization.
Hyaluronic Acid
- [Baumann, Ch. 32: Moisturizing Agents] Hygroscopic glycosaminoglycan that can bind over 1,000 times its weight in water; most abundant GAG in human dermis.
Panthenol
- [Baumann, Ch. 35: Anti-Inflammatory Agents] Dexpanthenol (provitamin B5) accelerates epithelial skin recovery and exhibits anti-inflammatory activity in skin.
Salicylic Acid
- [Baumann, Ch. 15: Acne] One of only three topical agents that treat existing acne lesions rather than just preventing future eruptions.
- [Baumann, Ch. 32: Moisturizing Agents] At low concentrations functions as a keratolytic and humectant; enhances penetration of other active ingredients.
Colloidal Oatmeal
- [Baumann, Ch. 32: Moisturizing Agents] One of the few botanicals labeled by the FDA as an effective skin protectant with anti-inflammatory properties.
- [Baumann, Ch. 32: Moisturizing Agents] Contains beta-glucan with immunomodulatory effects; has been used in traditional medicine for over 2,000 years.
Chemical Filter
- [Baumann, Ch. 29: Sunscreens] Chemical sunscreens absorb UV radiation via aromatic compounds conjugated with a carbonyl group.
Zinc Oxide
- [Baumann, Ch. 29: Sunscreens] Physical sunscreen that reflects and scatters both UVA and UVB; considered the broadest-spectrum single UV filter.
Well-Studied-tier ingredients
Tranexamic Acid
- [Bolognia, Ch. 55: Hyperpigmentation] Inhibits plasminogen activation in keratinocytes, reducing UV-induced melanogenesis and melasma severity.
Centella Asiatica
- [Baumann, Ch. 35: Anti-Inflammatory Agents] Asiaticoside and madecassoside stimulate type I firmer-looking skin support and inhibit inflammatory mediator production.
- [Baumann, Ch. 32: Moisturizing Agents] TECA (titrated extract of Centella asiatica) improves skin recovery and enhances skin barrier recovery.
Peptides
- [Baumann, Ch. 32: Moisturizing Agents] Copper peptide GHK-Cu enhances skin recovery, firmer-looking skin support, and sulfated proteoglycan levels.
Tea Tree
- [Baumann, Ch. 15: Acne] 5% tea tree oil gel was comparable to 5% benzoyl peroxide for acne with fewer side effects in a clinical trial.
Green Tea
- [Baumann, Ch. 33: Depigmenting Agents] EGCG has a stronger hypopigmenting effect than kojic acid; inhibits melanin synthesis by reducing MITF and tyrosinase.
- [Baumann, Ch. 34: Antioxidants] Polyphenols provide photoprotection and reduce UV-induced erythema through antioxidant and anti-inflammatory activity.
Alpha-Arbutin
- [Baumann, Ch. 33: Depigmenting Agents] Reversibly inhibits melanosomal tyrosinase activity; deoxyarbutin shows greater inhibition than the plant-derived form.
Vitamin E
- [Baumann, Ch. 34: Antioxidants] Primary lipid-soluble antioxidant in skin; 5% tocopherol cream reduced skin roughness and wrinkle depth vs. placebo.
Squalane
- [Baumann, Ch. 32: Moisturizing Agents] Natural skin lipid component that functions as an occlusive emollient without comedogenic effects.
Common questions
Does K-Beauty Oracle accept paid product placements?
No. Every product enters the catalog through the same automated sourcing pipeline and is scored by the same formula. There is no way for a brand to pay for inclusion or a higher ranking. The engine scores an $8 toner and a $45 serum identically in the scoring math.
How often does the product catalog get updated?
The catalog refreshes on a weekly schedule. New product searches run on Mondays, catalog comparisons run on Wednesdays, and Amazon freshness checks run daily. Products that go out of stock on Amazon are automatically penalized in scoring so they drop out of top picks.
Why does a product with a Traditional-tier ingredient sometimes still appear in my routine?
Evidence tier is one factor, not the only one. A Traditional-tier product (0.95x multiplier) can still outscore a Proven-tier product if it has very high concern scores for your specific skin issues and good texture compatibility with your skin type. The multiplier gap between Proven and Traditional (1.25x vs 0.95x) matters, but a strong concern match can overcome it. The engine also gives a small boost to products that pair well with what's already in your routine.
What data does the scoring engine use about each product?
Each product has concern scores (0-10 for each skin concern), a hero ingredient with an evidence tier, texture classification, potency rating, intensity rating, experience level tag, price tier, time-slot preference, formula confidence, formula source type, INCI data when available, sunscreen filter/cast metadata when relevant, and availability state. These fields are populated during the sourcing pipeline using ingredient analysis and formula review.
Can I see why a specific product made my routine?
Yes. Each product in your routine shows a reasoning line that explains why it was picked, referencing your primary concern and the product's hero ingredient. You can also expand any product slot to see alternative products that scored well for that step, along with options at different price tiers.
References
- Baumann, L. Cosmetic Dermatology: Principles and Practice, 2nd ed. McGraw-Hill, 2009.
- Bolognia, J.L., Schaffer, J.V., Cerroni, L. Dermatology, 4th ed. Elsevier, 2018.
See how our scoring works for your skin type and concerns.
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