How does one disable spellcheck on input type=text?

You can use either spellcheck=false or spellcheck="false" in an <input type="text">. This is a slight update to other answers posted.

jsfiddle.net/8nc2w6e0

Tested on Chrome 39.0.2171.95.

Updated Jan 2020

spellcheck=false and spellcheck="false" now both work in Chrome.

Original answer:

While spellcheck=false doesn't work in Chrome as mentioned in the question, spellcheck="false" works successfully.

From http://blog.whatwg.org/the-road-to-html-5-spellchecking#compatibility:

Google Chrome offers as-you-type spellcheck on <textarea> elements but not <input type=text> elements. It ignores the spellcheck attribute entirely. It does not offer the end user the option to change the default behavior or manually check individual fields.

So, it ends here.

---

Update: since Chrome 13 (released August 2011, 3 months after this answer), it's also supported on <input> elements.