In one liter there are 31.2 (UK) ounces. If that is the oz. Measure you are using, drink just slightly over 1 liter per day of water, (so just slightly more than two half-liter bottles of water).

If you're using US ounces as the measure, 1 liter is equal to 33.8 ounces, so drink just slightly under 2 half-liter bottles per day.

If you're using US ounces as the measure, 1 liter is equal to 33.8 ounces, so drink just slightly under 2 half-liter bottles per day.