Think Dirty vs ClearaScan: A 'Dirty' Score vs Your Triggers

Think Dirty rates cosmetics on a 1-10 'dirty meter'; ClearaScan checks against your own avoidance list. A fair, UK-focused look at how a clean-beauty score and a personal-trigger scanner differ, and who each suits.

The core difference

Think Dirty and ClearaScan both scan cosmetics, but they answer different questions. Think Dirty scans a product’s barcode and gives it a rating on a 1-to-10 “dirty meter”, folding health, allergen and sustainability concerns into a single number. ClearaScan does not rate products at all; it flags only the ingredients you have chosen to avoid. So the comparison is really a general clean-beauty verdict versus a personal-trigger check. Both have their place, and for sensitive skin the right choice comes down to whether you want a broad “cleanliness” read or a check against your own specific triggers.

How each one works

Think Dirty is popular in clean-beauty circles, especially in North America, and it works from its own criteria. It reads the barcode, assesses the ingredients against its rulebook, and returns one traffic-light-style score, along with “cleaner”-rated alternatives. The appeal is speed and simplicity: one number, easy to read, and a nudge towards products the app rates better. ClearaScan works the other way round. You save the specific ingredients you react to once, then scan any product, food, medication or cosmetic, and it flags only yours, making no general judgement of its own. It is currently in early access. The core difference is a universal score versus your personal list.

A fair point-by-point comparison

Coverage. Think Dirty has a large, mature cosmetics database built over years, so a mainstream product is likely to be recognised. ClearaScan is cross-category, covering cosmetics, food and medication, but as an early-access product its database is still growing.

How each judges a product. Think Dirty applies its “dirty meter” criteria, which blend several kinds of concern into one score. That is easy to read but inevitably subjective, and it reflects the app’s view rather than yours. ClearaScan makes no general judgement; it only checks against your list.

Personalisation. This is the heart of the comparison. A Think Dirty score is the same for everyone, so it cannot know your triggers. A product can score “clean” and still contain the exact compound that brings your skin out. ClearaScan starts from your triggers, so it flags what matters to you and stays quiet about everything else.

Cosmetic versus food. Think Dirty stays within cosmetics and personal care. If your triggers also appear in food or medicines, that is a gap. ClearaScan is built to check one list across all three categories.

Cost. Both have free versions with features that change over time, and ClearaScan is in early access. Check the current terms in each app.

Where each falls short. Think Dirty’s single blended score is a fine vibe check but not a personal safety check, and its clean-or-dirty framing is subjective. ClearaScan depends on you building an accurate list, and as a newer tool it has less coverage than an established scorer.

Who each one suits

Think Dirty suits someone who likes the clean-beauty framing and wants a quick general impression of a cosmetic, or who is looking for “cleaner”-rated alternatives to try. It is genuinely good at getting people to start reading their labels. ClearaScan suits someone who already knows their specific triggers and wants them caught quickly, especially in a shop, and whose triggers may span food, medicines and skincare. It also adds a Reaction Journal for flare-ups, a shared Care Circle so family or carers can scan for you, and a Trusted Products list for items you have cleared.

An honest recommendation

Think Dirty is a fine general scorer if you like the clean-beauty approach and want a fast overall read on a cosmetic. ClearaScan is the better fit when you need to know whether a product contains your specific triggers rather than how it rates in general. The honest trade-offs run both ways: Think Dirty needs no setup but gives a subjective, one-size verdict that cannot know your triggers, while ClearaScan is tailored to you but depends on you building the list and is still in early access with a smaller database. For many people the two sit comfortably side by side on the same phone, one for a general steer and one for the personal check. If you are not yet sure what flares your skin, neither app replaces advice from your GP or dermatologist, ideally with patch testing. (Disclosure: our editor co-founded ClearaScan, and we are not paid to mention the others.)

Written and reviewed by the Sensitive Skin Lab editorial team.