Our Methodology

1. Data sources

We use a three-tier source hierarchy. Higher tiers are always preferred and override lower-tier data when conflicts arise.

Tier	Source	Grade
1	Official brand website ingredient listing	A
2	Amazon product detail page (brand-managed)	B
3	User submission (community-sourced, pending review)	C / D

2. Editorial standards and independence

BuilderGel.app's editorial team reviews ingredient sources, normalizes ingredient names, applies the published status rules below, and records source and verification details where available. This is an editorial ingredient-source review, not a medical or clinical review.

Affiliate relationships, product price, marketplace rating, and commission rates do not affect ingredient status labels, confidence grades, or which ingredients are flagged. Products can appear without an affiliate link, and a purchase link is never evidence of safety.

Material corrections are prioritized when a brand changes a formula, a source becomes unavailable, or a reader provides a newer product label. Readers can use the submission form to report an error; the current physical label remains the final source to check before use.

3. Data confidence grades

Every product in our database is assigned one of four data confidence grades. This grade appears on product pages to help you understand how reliable the ingredient data is.

High confidence

Ingredient list sourced directly from the brand's official website or safety data sheet. Cross-referenced with physical product label where possible.

Good confidence

Sourced from Amazon brand-registered listing or equivalent third-party retailer with brand authorization. Not independently verified with physical label.

Moderate confidence

Community-submitted or scraped from non-authoritative source. Has been reviewed by our team but awaiting brand-level confirmation.

Low confidence

Unverified community submission or data older than 24 months without re-verification. Treat as indicative only — verify with physical label.

4. HEMA-free determination

A product is labeled HEMA-free on BuilderGel.app only if the following conditions are all met:

The ingredient list contains no HEMA (2-Hydroxyethyl Methacrylate) or any of its INCI synonyms
The ingredient list contains no Di-HEMA TMHDC (Di-HEMA Trimethylhexyl Dicarbamate) — a cross-reactive replacement that triggers HEMA allergy
The ingredient list contains no MMA (Methyl Methacrylate)
The ingredient list contains no HPMA (Hydroxypropyl Methacrylate)
The data confidence grade is C or higher

Note on "HEMA-free" labeling by brands: Some brands market products as "HEMA-free" while disclosing Di-HEMA TMHDC. HEMA-free describes the absence of HEMA only; it does not rule out other sensitizing methacrylates. We flag Di-HEMA TMHDC separately so readers can evaluate the full disclosure.

5. Ingredient status labels

Each product receives a descriptive ingredient status based on the disclosed ingredient list we reviewed. These labels are not medical advice and do not mean a product is allergy-safe for every user.

Label	Meaning
No flagged ingredients disclosed	Reviewed disclosure does not list HEMA, HPMA, Di-HEMA TMHDC, MMA, TPO, or other ingredients BuilderGel.app flags.
Low-concern ingredient disclosed	HEMA-free in reviewed data, but one low-concern ingredient is disclosed.
Medium-concern ingredient disclosed	One or more medium-concern flagged ingredients are disclosed; no high-concern ingredient is disclosed.
High-concern ingredient disclosed	One high-concern ingredient is disclosed, such as HEMA.
Multiple high-concern ingredients disclosed	Two or more high-concern ingredients are disclosed, such as HEMA plus Di-HEMA TMHDC.

6. Update frequency

Grade A (brand website) data is re-verified quarterly. Grade B data is re-verified every 6 months. Products with a data confidence grade of D are flagged for re-verification on the next update cycle. Formulation changes reported by users are prioritized for immediate review.

7. Non-medical-advice statement

BuilderGel.app is an educational resource. Nothing on this site constitutes medical or dermatological advice. If you have experienced an adverse reaction to nail products, consult a dermatologist or allergist for proper diagnosis and treatment. See our full disclaimer.

8. Reporting errors

If you notice incorrect ingredient data, a missing product, or a formula change that hasn't been reflected in our database, please submit a correction.

Submit a correction or new product