Atomic WebPage Size Calculator - Web page size and download speed calculator. Atomic Web Page Size Calculator is a Web page size and download speed calculator. Use it to ensure that visitors to your website are not waiting too long to download your pages. If they are, then they are most likely leaving before they read anything or buy anything from your site. Use it to calculate the size of your web pages and report on the download times that it will take to download your site on various connection speeds. Reports on 28.8Kpbs, 56kbps, 256kbps, 512kbps to simulate modems, ADSL and other high speed internet connections. Supports, Page, Images, JavaScript files.