Web map format overview

When you make and save a map using ArcGIS.com or Portal for ArcGIS, the map receives a unique ID. You can reference this ID to pull the entire map into any application you build with Esri APIs. This is made possible through the ArcGIS web map, a structured series of key-value pairs that describe all the layers, pop-up information, bookmarks, metadata, and other properties of the map.

Web maps are expressed in JavaScript Object Notation (JSON), a clear text format that can be easily transferred, stored, or manipulated. This section of the help explains how a web map is structured so that you can read or write web maps from custom clients.

There are two strings of JSON associated with a web map:

• The web map item information contains a title, description, and other metadata used to advertise the web map on ArcGIS.com or your own organization's portal.
• The web map data contains information needed to display the map, including layers, pop-up information, and bookmarks.

The web map and its specification should not be confused with the ExportWebMap specification, which is used by ArcGIS Server when printing maps. Although you may notice similarities in properties, they are two different specifications.