ECMAScript 5 compatibility table

http://kangax.github.io/es5-compat-table/#Object.keys

ECMAScript 5 compatibility table

 

 

	This browser		IE 9	IE 10, 11	FF 4+	SF 5.1	SF 6,7	WebKit	CH 13-16	CH 19+	OP 12	OP 12.10, 15	Konq 4.9	BESEN	Rhino 1.7
§Object.createc	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	No	Yes	Yes
§Object.definePropertyc	Yes		Yes	Yes	Yes	Yes	Yes	Yes[2]	Yes	Yes	Yes	Yes	No	Yes	Yes
§Object.definePropertiesc	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	No	Yes	Yes
§Object.getPrototypeOfc	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Object.keysc	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Object.sealc	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	No	Yes	Yes
§Object.freezec	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	No	Yes	Yes
§Object.preventExtensionsc	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	No	Yes	Yes
§Object.isSealedc	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	No	Yes	Yes
§Object.isFrozenc	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	No	Yes	Yes
§Object.isExtensiblec	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	No	Yes	Yes
§Object.getOwnPropertyDescriptorc	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	No	Yes	Yes
§Object.getOwnPropertyNamesc	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Date.prototype.toISOStringc	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	No	Yes	Yes
§Date.nowc	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Array.isArrayc	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§JSONc	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Function.prototype.bindc	Yes		Yes	Yes	Yes	No[4]	Yes	Yes	Yes	Yes	Yes	Yes	No	Yes	Yes
§String.prototype.trimc	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Array.prototype.indexOfc	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Array.prototype.lastIndexOfc	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Array.prototype.everyc	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Array.prototype.somec	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Array.prototype.forEachc	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Array.prototype.mapc	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Array.prototype.filterc	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Array.prototype.reducec	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Array.prototype.reduceRightc	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Getter in property initializerc	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Setter in property initializerc	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Property access on strings[5]c	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Reserved words as property names[6]c	Yes		Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	No	Yes	No
§Zero-width chars in identifiersc	Yes		Yes	Yes	Yes[7]	No	Yes	Yes	No	Yes	No	Yes	No	Yes	Yes
§Immutable undefinedc	Yes		Yes	Yes	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	Yes	Yes
§Strict modec	Yes		No	Yes[8]	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	No	Yes	No

^[1] In Internet Explorer 8 Object.defineProperty only accepts DOM objects (MSDN reference).

^[2] In some versions of WebKit Object.defineProperty does not work with DOM objects.

^[3] In Internet Explorer 8 Object.getOwnPropertyDescriptor only accepts DOM objects (MSDN reference).

^[4] Function.prototype.bind is now supported in Safari 5.1.4

^[5] For example: "foobar"[3] === "b"

^[6] For example: ({ if: 1 })

^[7] Firefox 4 & 5 fail this test

^[8] IE10 PP2 has a bug with strict mode which makes the following expression "fail", even though strict mode is more or less supported: (function(){ "use strict"; return !this })()