When you think of Zelda, most people tend to think of the series as a massive blockbust, but the truth is that very few games in the series have managed to sell more than five million copies (which roughly is what games like Gears of War and Metal Gear Solid sells - but a far cry from the likes of Call of Duty and Mario Kart), and they tend to be way more popular over here in the west than in Japan.
In fact, the only Zelda to sell more than one million copies in Japan was The Legend of Zelda: Ocarina of Time, which was released 20 years ago for the Nintendo 64. But now there's a new game that has the very same bragging rights - The Legend of Zelda: Breath of the Wild. According to Media Create, the Wii U version of the game has sold at least 133,024 (two-month-old numbers, so it has most likely increased ever so slightly) while the Switch version right now sits at 871,528 units.
These two combined is well over a million copies and we assume they won't stop selling anytime soon, and Breath of the Wild might even beat the Ocarina of Time for Nintendo 64 eventually which roughly has sold 1.5 million copies in Japan.
Goes to show just how popular the Switch and Breath of the Wild are in Japan.