One liter is usually equivalent to about 4 cups, but there are different kinds of cups. The measurement changes slightly depending on if one is using metric, U.S. customary, U.S. "legal," Canadian, Imperial, Japanese or traditional Japanese cups.
The simplest conversion is metric. One liter is equal to 4 metric cups. On the other hand, in America, 1 liter is equal to 4.22675283773 U.S. customary cups and 4.16666666667 U.S. legal cups. Canadian cups are slightly smaller, and 4.3993850 Canadian cups make 1 liter. Imperial cups are rarely used, but 3.52112676056 Imperial cups equal 1 liter. It takes five of the smaller Japanese cups to make 1 liter. And the traditional Japanese cup is even smaller; 5.55555555556 traditional Japanese cups make 1 liter.