The Map[@@toStringTag] property has an initial value of "Map". Property attributes of Map.prototype[@@toStringTag] Writable no Enumerable no Configurable yes Syntax Map[Symbol.toStringTag] Example Object.prototype.toString.call(new Map()) // "[object Map]" Specifications Specification Status Comment ECMAScript 2015 (6th Edition, ECMA-262)The definition of 'Map.prototype[@@toStringTag]' in that specification. Standard Initial definition. ECMAScript 2017 Draft (ECMA-262)The definition of 'Map.prototype[@@toStringTag]' in that specification. Draft Browser compatibility Desktop Mobile Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari Basic support 44.0 No support No support No support No support Feature Android Android Webview Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile Chrome for Android Basic support No support 44.0 No support No support No support No support 44.0