The film thins through wear, sweat, and UV-induced filter breakdown. Tell the calculator what you'll be doing — it will suggest a reapply window.
Protection thins over time — reapply before reaching the right edge.
Estimate the real-world SPF behind the number on the bottle.
See how much SPF foundation, powder, and setting spray actually deliver.
Live UV, burn windows, and how reflective surfaces change your risk.
A behavioural snapshot of cumulative UV risk over time.
Calm, clear photoprotection after retinoids, peels, and procedures.
This tool is for educational purposes only and is not medical advice. Estimates are derived from peer-reviewed dermatology literature, ISO 24444 SPF testing methodology, and consensus photoprotection guidance. Always consult a qualified healthcare professional or dermatologist regarding skin concerns, sun exposure, or post-procedure care.