The World Wide Web Consortium (W3C) has set 2014 as the date for final approval of HTML5 for web operations.
The HTML Working Group will issue its last call for technical information and conflict data among participants this May, and testing will run for the next three years to check the specification's resilience.
Experts have warned that HTML5 is being keenly checked by malware writers and that proper testing is vital.
"Even as innovation continues, advancing HTML5 to Recommendation provides the entire web ecosystem with a stable, tested, interoperable standard," said Jeff Jaffe, W3C chief executive.
"The decision to schedule the HTML5 Last Call for May 2011 was an important step in setting industry expectations. Today we take the next step, announcing 2014 as the target for Recommendation."
Some 50 organisations and more than 400 individuals have participated in the standard so far, the W3C said, and software firms have been invited to send in testing suites to be used during the final bug-checking process.
The time being taken to get HTML5 ratified is causing some concern within the industry, not least with Google. The provision of video standards on the new HTML framework is key to a fight over open source code between its supporters and an alliance of Microsoft and Apple.
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