We regularly audit our data usage calculations, examining server logs in order to determine whether session by session, day by day, correct usage statistics are being stored and shown. It's important to note that all imagery downloaded from our server to your computer contributes to data usage, not just when using the Export function.
Here's how to confirm the accuracy of Nearmap's data usage calculations in Chrome or Internet Explorer:
On a PC, press F12 to bring up the Developer Console in the lower part of the browser window. On a Mac, press Option-Command-I.
Switch to the Network tab to see a status bar on the bottom of the browser window that indicates the data transferred.
If you're using Internet Explorer, you can also reach the developer console using F12. Click the Network tab, then click the Play button to start tracking traffic. The data received is shown on the right side of the bottom status bar.