Start by selecting Plan & Track in the top left of the screen, then select Track Quantities. The Cut/Fill heatmap will load. When comparing a scan to a previous one, the red color marks areas that were raised (filled). The blue color marks the areas that were lowered (cut). White areas indicate regions where there was almost no change in the elevation between the two dates compared. There is a scale for the heatmap colors in the lower-right corner of the window.
To quantify a specific area, select the starting point of what you want to be measured. Continue to click to outline what are you want to cover. When you have determined the endpoint, click the checkmark. Your calculations appear in a new window. By default, you will see the volume of the dirt moved between the last two dates: the scan visible on your map and the previous one. You can select another date to compare to from the drop-down menu.
The relative tab shows the amount of dirt moved (cut and filled) between selected flyovers. Using the cumulative tab may be valuable when you need to get the accumulated cuts and fills between each of the consecutive scans within a wide range of dates: for example, if you would like to evaluate the volume of dirt that was moved twice between the selected dates. For that, choose the earlier scan from the drop-down menu. And then click "Recalculate" to update the measurement.
Clicking Save Cumulative will save the boundaries of your selection so you can refer to the same area as the project progresses. See Saved Quantities in the sidebar to find your saved measurement. To learn more about how to save these kinds of measurements, see the Saved Quantities topic in this guide.