According to Jeff Klee, CEO of CheapAir, the perfect day to book airfare is precisely 54 days in advance, on the dot.
In a study from earlier this year, CheapAir analyzed the data of 921 million fares. The company found that, between 320 and 106 days before a trip, plane tickets tend to hover at a static price.
However, at the 105-day mark, price start dropping, until they reach a nadir at 54 days, before ticking back up. Then, at the 20-day mark, prices dramatically increase.