macbook temperature

Hello people, I just get my first MacBook and I was interested in comparing MacBook temperature with someone, just to make sure it works properly. its 2017 model 15 inch 2.9Ghz. when I use it in safari and maybe pages together temperature goes between 30-40. I didn't use it on heavy load. when I updated it on high Sierra it got really hot, I felt warm on my keyboard. is it normal or I should visit store.