How to use SubtleCrypto in chrome (window.crypto.subtle is undefined)

It would appear you have to use sites with https://...... and not vanilla http://....

From the spec - easy to miss (and linked by Zmart, above):

Access to the WebCrypto API is restricted to secure origins (which is to say https:// pages).

According to the spec (via Github issues) a la this Google page for WebCrypto:

crypto.subtle is supposed to be undefined in insecure contexts

check your URL's

if it is https://localhost:PORT or 0.0.0.0:port or 127.0.0.0:port

change it to proper hostname URL something like http://localhost:PORT

worked for me! Thanks @Zmart