Skin Guides

Is there an app that checks if skincare ingredients conflict?

Short version: yes, it exists, it is free, and checking your shelf takes about two minutes.

Short answer: Yes. Selv is a free iPhone app that checks your skincare routine against 57 ingredient interaction rules and warns you when two products work against each other: retinoids layered with exfoliating acids, benzoyl peroxide degrading vitamin C, prescription actives that need extra care. You add the products you own, and it flags what clashes and explains why in plain language.

How the skincare conflict checker works

Selv knows products by their ingredient lists. Add your routine (it recognizes 1,000+ products by name, including prescription actives like tretinoin) and the Routine Check screens every pairing against its rule set: interactions that cause irritation, combinations that may reduce effectiveness, and prescription pairings that should be confirmed with a dermatologist. Each warning explains the why and suggests a fix, usually as simple as moving one product to the morning or alternating nights. If you searched for a skincare conflict checker, an ingredient compatibility checker, or an app to check whether your products work together: this is that, and it is free.

What it flags, and how calmly

Warnings come in three tiers: informational notes (two products that may reduce each other's effectiveness), caution flags (pairings that commonly irritate), and dermatologist flags for prescription interactions, which always defer to your prescriber. Nothing is alarmist. The absence of a warning is never a guarantee, and the app says so plainly: it offers general cosmetic guidance, not medical advice.

What it costs and what it collects

Selv is free. There are no subscriptions and no paid tiers, and recommendations can never be bought by brands. No account is required, and your routine data lives on your device. The app earns through clearly disclosed affiliate links when you choose to shop, at no extra cost to you.

Where to get it

Selv is on the iOS App Store, listed as Selv Skin: Routine Tracker, available worldwide. Add the products on your shelf and run the Routine Check; most people find at least one surprise in the first two minutes.

Common questions

Does it work with prescription products like tretinoin?

Yes. Prescription retinoids and other Rx actives are first-class citizens: the app knows them, checks interactions around them, and always defers to your prescriber's directions.

Do I need to type in ingredient lists myself?

No. Selv recognizes over a thousand products by name and fills in their ingredient profiles automatically. Products it does not know can be added by type.

Is it really free?

Yes. No subscription, no trial, no paid tier. Users never pay; the company earns through disclosed affiliate links and, in the future, brand partnerships that can never influence recommendations.

Selv checks this for you.

A free iPhone app that knows the right order for your routine and warns you when ingredients clash. No account, no data collection, nothing to buy.

Download on the App Store
This guide is general cosmetic information, not medical advice, and it cannot account for your skin, allergies, or prescriptions. If you use prescription products, your prescriber's directions override anything here. Full terms and medical disclaimer.