That’s the promise of a new website, called Jet Lag Rooster, which uses real science to help you conquer jet lag. How does it work? First, the site asks for your flight information, including your departure city and time, as well as your arrival city and time. Then, it asks when you normally go to sleep and wake up when you’re home. And whether you’d like to start shifting your sleep schedule before you travel, or after you arrive.

Once you’ve plugged in all the information, the site gives you a custom “jet lag plan,” which includes an exact day-by-day sleep schedule. But more importantly, the plan also tells you the best times each day to seek as much bright light as possible – whether it’s daylight, or indoor artificial light – and also when to avoid light.

Why is that a big deal? Because research shows that bright light is a key factor in regulating our body’s circadian rhythm. It’s what wakes us up each morning, and keeps us feeling energized throughout the day. But when we travel, our biological clock is out of sync with the daylight around us. So, we wake up earlier, or stay awake later, than we’re used to. And that’s when jet lag sets in – which is linked to everything from fatigue and cognitive problems, to an increased risk of depression, and even trouble going to the bathroom!

So, does Jet Lag Rooster work? Dr. William Kohler directs the Florida Sleep Institute, and he says “yes.” In fact, Dr. Kohler recommends using tools like Jet Lag Rooster before considering anything else – like taking melatonin.