This meter seems to work. I used this for testing outdoor UV levels and the protection provided by various windows and sunglasses.
However, at noon in the middle of summer, pointing at the sun, the highest reading I read was 4.5, though the sun wasn't that strong.

This review is for the UV Meter sold by TOPCHANCES. To jump to the conclusion first: I give this 5 stars. Well made. Easy to hold. Simple to operate. Light. Small--easy to carry in a purse or pocket. Most importantly--provides key info on UV so you can make smart decisions about protecting your skin. When I was a kid, no one wore sunscreen. In the summer, the way you protected your skin was to get a tan. Now I see a dermatologist twice a year and have had one basal cell carcinoma removed and a number of precancerous cells removed, all caused by exposure to ultra violet light. In fact, according to the National Institute of Health, BCC is the most common cancer diagnosed and the incident rate continues to increase. Since I spend a lot of time outdoors, walking 2-3 miles every day, hiking in the mountains, family time at the beach, plus attending a lot of kid's activities, I thought this meter could provide info that can be used to take the correct safety precautions, whether it's simply wearing a hat or using sunglasses or deciding to stay indoors. The meter itself is pretty simple to set up: you set the date and clock and you're ready to go. It comes with batteries already installed (as well as a backup set to use later) so you can walk outside, push a button, and get an instant UV reading. You can also test how protective your sunglasses are and even sunscreen by rubbing some on clear glass and taking a reading of the sunlight passing through the glass. The meter is on the expensive side, but it raises awareness about an important health issue that most people ignore. Personally, I think it's worth the price and will pay health benefits for my family for years to come. By the way, the meter shown on the Amazon page is yellow; mine is orange.