Here you can paste in URLs for products on amazon.com and amazon.co.uk and you’ll be given back a URL that will redirect UK visitors to amazon.co.uk and others to amazon.com. There’s nothing to install on your site and there’s no messing in markup - just paste a hyperlink in the way that you normally would. There are also separate fields for your affiliate IDs which means you can paste in any old Amazon link without having to ensure your affiliate tag is in there. They’re also persisted to local storage so next time you come back they’re pre-filled!
In addition to pasting URLs you can enter ASIN numbers or search terms directly (did I mention you can paste in search results URLs too? it’ll parse them!). A banner is shown beneath each box explaining exactly what will happen to visitors for this region.
The URLs will automatically combine similar info to keep them short, so if the ASIN or search terms are the same, or if your affiliate tags are the same for UK and US (except for the -20 and -21 suffix) they will be combined and handled during the redirect.
It will even shout at you if you enter invalid URLs or affiliate tags to ensure you’re not messing up.
The URLs are simple to build yourself too, the format is described on the site.
If you’re an Amazon affiliate check it out, I’d love feedback. It’ll work for non-affiliates too if you’d still like to send visitors to the correct site (or if you’re only an affiliate in one region, it’ll still work).