The toolkit
Interactive tools
Specific answers without scrolling through articles. Every tool is grounded in published cosmetic-science protocols.
Featured
Free Acid Calculator
Henderson–Hasselbalch model — estimate bioavailable free-acid % and exfoliation intensity.
Concentration Guide
Match a glycolic % to your skin goal and experience level.
AHA Comparison
Compare glycolic, lactic, mandelic, citric, and tartaric side-by-side.
Ingredient Checker
Spot conflicts and compatible pairings in your routine.
Frequency Calculator
Build a safe ramp-up schedule based on your strength.
Skin Type Quiz
Get a glycolic protocol matched to your skin type.