What the UV index numbers mean
A quick guide to UV index levels and what to do at each one.
The UV index is a simple scale that tells you how strong the sun’s ultraviolet rays are right now. The higher the number, the faster your skin can burn. Here is what each range means.
The scale at a glance
- 0 to 2 (Low). Minimal risk. Most people can stay outside safely.
- 3 to 5 (Moderate). Take care around midday. Seek shade and wear sunscreen.
- 6 to 7 (High). Protection needed. Cover up, wear a hat, and reapply sunscreen often.
- 8 to 10 (Very high). Extra care. Avoid the sun in the middle of the day where you can.
- 11 and above (Extreme). Unprotected skin can burn in minutes. Stay in the shade.
Why UV Timer uses it
UV Timer combines the live UV index with your skin type to estimate how long you can stay out before burning. A higher index means a shorter safe time, which is why the timer changes through the day.
Tip: UV is strongest between late morning and mid afternoon, even on cloudy days. Check the app before you head out.