How Much Is a Part Per Million? Visualizing activity answer: One sheet of 8 1/2 x 11-inch paper is 603.2 square centimeters. So you could fit just over 603 little squares on a single sheet. To make that little square be one part per million, you would need 1657 sheets of paper. To make that little square be one part per billion, you would need 1,657,000 sheets of paper! Facebook Pinterest Twitter © 1997 – 2019 Journey North. All rights reserved.