For reference, an open source library using a similar approach (crytpo + asm.js): https://github.com/vibornoff/asmcrypto.js/ https://github.com/vibornoff/asmcry

For reference, an open source library using a similar approach (crytpo + asm.js): https://github.com/vibornoff/asmcrypto.js/ https://github.com/vibornoff/asmcrypto.js/ Looks like the asmcrypto's speed boosts are pretty high relative to SJCL and CryptoJS. Granted, this article's approach is transpiles C->JS, not sure what the implications are there in terms of performance.