Free · Science‑backed · Private

Your serums might be
fighting each other

Instantly check for ingredient conflicts backed by CIR, PubMed, and dermatology consensus. No sign‑up, 100% private.

🧪 Live Demo — Check all conflicts (12 actives + custom input)
Retinol Glycolic Acid (AHA) Salicylic Acid (BHA) Vitamin C Niacinamide Benzoyl Peroxide Copper Peptides Gluconolactone (PHA) Azelaic Acid Hyaluronic Acid Ceramides Matrixyl (Peptides)
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Features

Science you can trust

Every conflict rule is linked to published research or regulatory assessments.

Evidence‑based rules

All 9 built‑in conflict checks are derived from CIR safety reports, PubMed studies, and EU CosIng restrictions. Each result shows its source.

Instant Full Scan

Select all your actives at once. SkinClash scans every possible pair and lists all conflicts in seconds — not just the first match.

Smart autocomplete

Fuzzy search (Fuse.js) with INCI aliases ensures you always select the correct ingredient.

100% Private

All checks run locally. No data leaves your browser.

Who's It For

🧴 Skincare newbies — Learn what not to mix.
🔬 Routine stackers — Audit your 5+ serum lineup.
🎥 Beauty creators — Answer follower questions instantly.

Conflict rules

9 rules, each with a reason and reference

PairRiskWhy it clashesFixSource
Retinol + Glycolic Acid (AHA)HighBoth accelerate cell turnover → over‑exfoliationAlternate nightsCIR, 2025
Retinol + Salicylic Acid (BHA)HighCombined exfoliation overloads the epidermisSeparate day/nightJ Cosmet Dermatol, 2023
Retinol + Benzoyl PeroxideHighBenzoyl peroxide oxidizes retinol → both inactiveAvoid layeringDermatol Ther, 2022
Vitamin C + NiacinamideMediumpH mismatch may form niacin → temporary flushingWait 10‑15 minInt J Dermatol, 2021
Vitamin C + RetinolMediumRequire different pH environments → mutual irritationAM / PM splitJ Clin Aesthet Dermatol, 2022
Copper Peptides + Vitamin CMediumVitamin C oxidizes copper → reduced anti‑aging effectAlternate AM/PMDermatol Surg, 2023
Niacinamide + AHAMediumAcidic pH converts niacinamide to niacin → stingingApply at different timesCutis, 2022
AHA + BHAMediumDual acid exfoliation strips the moisture barrierChoose one per routineEgyptian expert consensus, 2024
Benzoyl Peroxide + Vitamin CLowMild oxidation → slightly reduced potencySeparate by time if toleratedJ Am Acad Dermatol, 2023
⚕️ Medical Disclaimer
SkinClash provides educational information based on published scientific literature. It does not replace professional medical advice. Always consult a dermatologist before starting new skincare routines. Report inaccuracies: hello@skinclash.com.
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FAQ

Science & safety

Where do the conflict rules come from?
All rules are based on publicly available CIR safety assessments, PubMed-indexed studies, and the Egyptian expert consensus on combining active ingredients (2024). Each result shows its specific reference.
How do you ensure ingredient accuracy?
We use a controlled vocabulary with INCI names and common aliases, combined with Fuse.js fuzzy matching, to correctly identify user‑entered ingredients.