A few years ago, I discovered the site Simply Noise. With just a few clicks, it plays white noise and even pink or brown noise on your computer (there’s an app, too).
This website saved me many times when I was in a noisy office, or when people in the cubicles next to me were chatting and I couldn’t concentrate to save my life.
Just the other day, I was working a cafe, and the guy next to me was sniffing and snorting with a runny nose. I don’t know why he didn’t just blow his nose, but I felt like I could hear his copious snot rattling around every 10 seconds. Disgusting. A brief dirty look didn’t help, and then I remembered Simply Noise. Thank goodness!!!! I turned the volume up to the max.
If you have trouble focusing, check it out! They also have a site called Simply Rain.