SPF or RIP

Privacy & Terms

Last updated: May 2026. Welcome to SPF or RIP, Atlanta's premier sunburn countdown tool and unsolicited dermatology opinion service.

What We Collect

Nothing personally identifiable. Your skin type, SPF selection, medication flag, and reapplication timer state are saved locally on your device (localStorage) and never leave your browser. The browser service worker (sw.js) caches static assets (HTML, icons, manifest) using the browser's Cache API for offline support — no personal data is cached. We use GoatCounter for anonymous page-view analytics — it counts visits without cookies, fingerprinting, or personal data.

UV Data

UV index and temperature data is sourced from Open-Meteo, a free and open meteorological API, for Atlanta, GA (33.75°N, 84.39°W). Requests are routed through a Cloudflare Worker at burn.madebyaaron.app, which caches the Open-Meteo response for up to 5 minutes — your browser never connects to Open-Meteo directly. Cloudflare's privacy policy applies to those requests.

About the Calculations

Burn times are estimated using the Fitzpatrick Minimal Erythemal Dose (MED) model. UV irradiance is estimated at 25 mW/m² per UV Index unit. Effective exposure time with sunscreen = unprotected time × SPF. These are theoretical estimates; actual burn times vary with cloud cover, reflection, application coverage, and the sun's personal feelings about you. WHO (2002). Global Solar UV Index: A Practical Guide. Fitzpatrick TB (1975). Soleil et peau. Journal de Médecine Esthétique. Diffey BL (2002). Sources and measurement of ultraviolet radiation.

Sunscreen reapplication windows follow FDA sunscreen regulations (21 CFR Part 352): 2 hours for standard sunscreen, 80 minutes for water-resistant formulas.

Pavement temperature estimates are based on research showing asphalt reaches 40–60°F above ambient air temperature on sunny days, scaled by UV index. The 5-second hand test is recommended by the American Veterinary Medical Association (AVMA). AVMA. Warm Weather and Your Pet.

Reapplication Timer

Timer state is saved locally so it persists through page refreshes. When a timer is running, the browser service worker schedules a notification independently of the page tab — meaning it can fire even if you've switched apps, as long as the browser itself is still running. If the browser is fully closed, the notification won't fire. Timer data is removed from localStorage as soon as the timer expires or is reset. We are not a push notification service. The sun does not grade on a curve.

A Note on Medications

Certain medications make you significantly more sun-sensitive than the Fitzpatrick model can account for — including doxycycline (extremely common), some blood pressure meds, diuretics, retinoids, and certain chemotherapy drugs. The effect varies so widely by drug, dose, and individual that there's no single reliable multiplier we could apply to the burn time estimate. So we don't try. If the "I take photosensitizing medication" box is checked, the burn time estimate is replaced with a warning instead of a number. Talk to your prescriber about sun exposure before heading out. We are not equipped for that conversation and neither is a website with a cartoon sun.

Feedback

The Feedback link opens a mailto to a real human who reads every message. Bug reports, feature ideas, and sunburn stories are all welcome.

Limitation of Liability

SPF or RIP is a sunburn awareness tool, not a medical device. It is provided "as-is," with no warranty — express, implied, or cosmic — that the numbers are correct for your specific situation, biology, or relationship with the sun. We are not your dermatologist. By using this app you accept that sun exposure is your call, your skin, and your consequence. We are not responsible for peeling, redness, premature aging, regret, or the look your doctor gives you at your annual skin check. If you have a photosensitivity condition or unusual sun sensitivity, please consult an actual professional who went to school for this. Apply sunscreen. We mean it.

📱 Add to Home Screen

Install SPF or RIP for one-tap access from your home screen — no App Store required.

Step 1

Tap the Share button (📤) at the bottom of Safari.

Step 2

Scroll down in the share sheet and tap "Add to Home Screen."

Step 3

Tap "Add" in the top right. Done — it'll appear on your home screen like any other app, with full-screen support and reapplication notifications.