--- title: "Sunscreen Reapply Timer: When to Reapply | Rose Quartz Glow" description: "A sunscreen reminder that counts down to your next coat: every 2 hours, or sooner after swimming, sweating or towel drying, with optional alerts." url: https://rosequartzglow.beauty/sunscreen-reapply-timer/ --- Every 2 hours · sooner in the water # Sunscreen reapply timer Start the timer when you put sunscreen on. It counts down to the next coat using the reapplication rules printed on sunscreen labels, and keeps time even if you close the tab. Timer not running Choose what you are doing, then press “I've just put sunscreen on”. ## Alerts Optional. Your browser will ask for permission first. Alerts show while this page is open in a tab (even in the background); the countdown and the tab title change either way. ## Today's coats None yet. Times are kept only in this browser. ## How the reapply timer works 1. **Say what you are doing.** “Staying dry” counts down 2 hours, the longest gap the US label directions allow (“reapply at least every 2 hours”). “Swimming or sweating” starts the water-resistance clock as well. 2. **Pick the label's water resistance.** US labels may only say “Water Resistant (40 minutes)” or “(80 minutes)”: the time the stated SPF lasted in the test while swimming or sweating. With either, the timer asks for a new coat after that many minutes in the water, or after 2 hours if that comes first. If your sunscreen claims no water resistance, the timer warns you to reapply as soon as you leave the water. 3. **Press “I've just put sunscreen on”.** Press it again after each coat to restart the countdown. Forgot to start it? Enter the time you applied it instead. 4. **Towelled off?** The label says to reapply immediately after towel drying, so that button makes the next coat due straight away. **Example:** you put on a sunscreen labelled water resistant (40 minutes) at 10:00 and stay on the sand. The timer says 12:00. At 10:30 you go swimming and switch to “Swimming or sweating”: the next coat moves to 11:10, 40 minutes into the swim. If you towel dry at 10:55, it is due at once. The countdown is worked out from saved times, so it stays right if the tab sleeps, the phone locks or you reload the page. ## Where the rules come from The US FDA's sunscreen rule fixes what labels must say: water-resistant products tell you to reapply “after 40 minutes” or “after 80 minutes of swimming or sweating”, “immediately after towel drying” and “at least every 2 hours”; products that are not water resistant say to reapply at least every 2 hours and to use a water-resistant sunscreen if swimming or sweating. The words “waterproof” and “sweatproof” are not allowed. Dermatologists say much the same. The American Academy of Dermatology advises reapplying every two hours and immediately after swimming or sweating; the British Association of Dermatologists, every two hours and after swimming, towel-drying or sport, even for “once a day” products, since patches get missed or rubbed off. A higher SPF does not stretch the interval: SPF describes how much UV a layer blocks, not how long it lasts. ## Questions about reapplying sunscreen **Does SPF 50 last longer than SPF 30?** No. The FDA points out that SPF relates to the amount of sun exposure, not to time. Sunscreen wears off through sweat, water, rubbing and towels whatever its SPF, so the 2-hour rule is the same for both. **What does “water resistant (40 minutes)” mean?** In the FDA test, volunteers wear the sunscreen through two 20-minute spells of moderate activity in water, with a rest in between, and it must still give the labelled SPF afterwards. The 80-minute claim needs four such spells. No sunscreen is waterproof, and US labels may not say so. **What about sunscreens sold as “once a day”?** The British Association of Dermatologists still recommends reapplying every two hours whatever the product, because it is easy to miss patches or rub the sunscreen off. The EU recommendation also says sunscreens should not claim that no reapplication is ever needed. **Will the timer still work if my phone locks?** The countdown will: it is calculated from the saved time you applied sunscreen, so it is correct whenever you look. Alerts are different. They can only appear while the page is open in a tab, a sleeping background tab may show them up to a minute late, and some phones only allow alerts from installed apps. **How long before going out should I apply it?** US labels say 15 minutes before sun exposure. The BAD suggests 15 to 30 minutes before going out and a second coat 15 to 30 minutes after, and the NHS suggests 30 minutes before and again just before you go out. The second-coat option covers that extra layer. ## Sources - US FDA, [21 CFR 201.327](https://www.ecfr.gov/current/title-21/chapter-I/subchapter-D/part-201/subpart-G/section-201.327): label directions (reapply wording, 15 minutes before exposure), water resistance statements and the water resistance test. - US FDA, [Sunscreen: How to Help Protect Your Skin from the Sun](https://www.fda.gov/drugs/understanding-over-counter-medicines/sunscreen-how-help-protect-your-skin-sun) (reapply at least every two hours; SPF relates to the amount of exposure, not time; no waterproof sunscreen). - American Academy of Dermatology, [How to apply sunscreen](https://www.aad.org/public/everyday-care/sun-protection/shade-clothing-sunscreen/how-to-apply-sunscreen). - British Association of Dermatologists, [The sunscreen fact sheet](https://www.skinhealthinfo.org.uk/sun-awareness/the-sunscreen-fact-sheet/) and [Sun protection advice for children and babies](https://www.skinhealthinfo.org.uk/sun-awareness/sun-protection-advice-for-children-and-babies/) (two coats; every two hours; once-a-day products). - NHS, [Sunscreen and sun safety](https://www.nhs.uk/live-well/seasonal-health/sunscreen-and-sun-safety/). - European Commission, [Recommendation 2006/647/EC](https://eur-lex.europa.eu/eli/reco/2006/647/oj/eng) (no “all day” claims).