You can even insert the canonical URL into your HTTP header on the website page (this part is visible only by web browsers) The JS redirect sounds like a little bit of a messy situation, but to reply your dilemma: When you set a canonical tag from ourdomain.be to ourdomain.be/en, https://socialrus.com/story18205782/rumored-buzz-on-tag-hreflang-automatici-e-tag-canonici-seo