The official ECMAScript 5th Edition standard can be downloaded as a PDF file from the Ecma Web Site
ECMAScript 5.1 is a maintenance revision of the ECMAScript 5 specification. It corrects technical and editorial errors and its content is identical to the proposed ISO edition of the ES5 specification. This is intended to be the final draft, it has been approved by TC39 and is awaiting the completion of the ISO and Ecma standardization processes.
This document was approved on September 23, 2009 by Ecma TC39 as the final specification for ECMAScript, Fifth Edition. This specification has been forward to the Ecma General Assembly for their approval as an Ecma International standard.
Approval Draft This is the draft to be reviewed for final publication approval at the September 23, 2009 TC39 Meeting.
This version is identical with Release Candidate 3 but has been assigned ECMA document #TC392009/040. Any errata identified prior to the Sept. 23 meeting will be listed here:(revised Sept. 22) doc pdf. Draft with all post Sept 1 changes including markup: doc
These are the final technically frozen drafts that use current ECMA formatting conventions. Review feedback is requested on formatting and typographic issues and any technical errors or inconsistencies.
Candidate Specification Final Draft (April 2009 Candidate Specification) ECMAScript, 5th Edition
This the Candidate Specification Release.
Feedback and Errata for Candidate Specification
Conformance Test Suite