"This means that engines that support asm.js light up the new features, while engines that don't will simply run with degraded performance," the company said.
"Asm.js is a clear step towards enabling near-native performance for the web platform, which is why we're excited to bring it to Chakra in an upcoming release."
Mozilla developer Luke Wagner said that momentum is starting to build behind asm.js.
"This is a strong vote of confidence by Microsoft in asm.js and the overall compile-to-web story," he said. "I look forward to collaborating with Microsoft and other browser vendors on taking asm.js to new levels of predictable, near-native performance."
With the addition of IE, support for asm.js will eventually appear across all three major browsers used today -- Firefox, Chrome, and IE.