If you want to compare two web maps side-by-side, here’s a quick and easy way to accomplish that in just a few steps.
First, find the web maps that you want to compare side-by-side. In this example we went to the ArcGIS Online Gallery and wanted to compare two maps we found there – USA Median Household Income and USA Unemployment Rate.
Did household income come into play with the unemployment rate? We wanted to compare the maps visually to learn more.
Step 1: Open one of the maps that you want to compare, in this case we’ve opened USA Median Household Income. Each map has an ID. Like your social security number or driver’s license, this ID is unique and can be used to reference the map. You’ll find the ID in the URL for the map. Highlight and copy the map ID.
Step 2: Open the second map you want to compare, in this case it’s USA Unemployment Rate. Once opened, click Share, then choose Make a Web Application.
Step 3: Locate the Swipe Tool (currently found on the 3rd page of the template gallery).
Step 4: Click the arrow next to publish, and choose Preview as shown below:
Step 5: After opening the Swipe Tool in preview mode, add a comma at the end of the URL (after the map ID) and paste the map ID you copied in the first step above after the comma (omitting any spaces).
Hit carriage return, and now you have a quick visual comparison of two maps using the Swipe Tool template. Grab the red line with your mouse and move it back and forth to compare the two maps.
You can save or share the URL you’ve pasted together, and as an alternative you can also host the Swipe Tool application and configure it to use both web maps if you want to author a more permanent comparison. This same technique also works with other comparison templates, such as Compare maps.
For more information see About using web maps.