Blackout curtains serve a variety of purposes, including blocking out sunlight, reducing outside noises, and controlling temperature. To find the best blackout curtains, I tested a range of options with different fabrics and hanging methods. I also measured their effectiveness in blocking out light and regulating temperature and noise. After a week of testing, I found that the curtains with additional lining and multiple hanging options were the most effective. When shopping for blackout curtains, it’s important to consider the size and installation method that best suits your needs. Overall, blackout curtains are a great investment for those looking to improve their sleep quality and create a more comfortable living space.