CosDNA flags ingredients in theory.
ClearSkin shows the ones breaking you out in practice.
CosDNA is a useful screening filter, with comedogenic and irritant ratings on every ingredient. ClearSkin is the ground-truth layer underneath: a daily log of the products you actually use, correlated with your breakouts, so a 5/5 flag in a great formula and a 2/5 in a harsh one both get tested against your skin instead of a table.
Free. No account required.
Ratings are a hypothesis, not a verdict
A 5/5 comedogenic ingredient at 0.1% in a well-buffered formula may be fine for you. A 2/5 at 25% may not. CosDNA cannot tell the difference. ClearSkin watches your skin and shows you which usage actually lines up with breakouts.
Ingredient logs by day, not by table
You log the products. ClearSkin records every ingredient and the days each one was on your face, then surfaces the ones that line up with your worst weeks. No static rating can do that, only your own log can.
On-device, no account, free
Everything stays on your phone. No sign-up, no community profile, no cloud sync, no paywall. You can use the entire app offline and delete it without leaving anything behind on a server.
Built around the research
Categories and prompts are based on what peer-reviewed studies show actually drives acne, not on a single 1972 rabbit-ear data set or a community ranking.
Frequently asked questions
Are CosDNA's comedogenic ratings reliable?
Somewhat. They are a starting hypothesis, useful as a first screen when picking a product. They are not a verdict. Concentration, pH, vehicle, and your own skin all change the outcome. The only honest test is to track what you actually use against your actual breakouts, which is exactly what ClearSkin does.
Does ClearSkin rate ingredients like CosDNA does?
No. ClearSkin does not assign ingredients a 1-to-5 rating. Instead, it tracks what you use and whether your skin responds, then surfaces the ingredients and habits that line up with your breakouts. The verdict comes from your data, not from a fixed table.
Is ClearSkin free?
Yes. There is no paid tier, no in-app purchase, no subscription. Every feature is available from day one. ClearSkin is designed to be used until you have your answer and then closed, not to keep you paying month after month.
Is my data private?
Yes. Everything stays on your phone. There is no account, no sign-up, no cloud sync, no telemetry, and no community profile. You can use the app entirely offline, and deleting it removes your log completely because nothing was ever stored on a server.
- Static comedogenic and irritant ratings
- Ratings from 1972 rabbit-ear data
- No formulation context (concentration, pH, vehicle)
- No tracking of your actual usage
- No personal correlation
- Web-only
- Tracks ingredients in your real routine
- Adds the days you used each one
- Surfaces patterns over weeks of data
- Habits and ingredients in one view
- On-device iOS app, no account
- Free, no paid tier
Pair the screening filter with the personal log.
Use CosDNA to flag what might be a problem. Use ClearSkin to find out which of those ingredients actually is one for you. Free on iOS.
Free. No account required.