Google’s John Mueller said it doesn’t hurt you to used mixed languages in your URLs but it might confuse users who look at your URLs. John was asked on Twitter “Mixing language in url path” is it bad? John said “I don’t see a problem with that.”

John did add “However, if you’re making URLs for your users, then I’d recommend making them so that your users understand them.”

Here are those tweets:

Google does look at your keywords in your URLs, but it is a tiny tiny ranking signal.

Forum discussion at Twitter.