MiniDisplayPort to HDMI Active Adapter –4K
1 If your Mac doesn’t have an HDMI port, you’ll need an Mini DisplayPort adapter to plug it into a 4K television. Ensure you pick one that supports displays up to 4K, not just 1080p. Like most, this one leaves you to add a HDMI cable. Its HDMI port limits output to 30Hz, but that’s good enough to use your TV to preview, say, 4K projects from Final Cut Pro X. Shop around because the suggested price is higher than an alternative sold by Apple, but we've seen this one online for £18. Alan Stonebridge
A good and inexpensive way – if you shop around for the best price – to connect a Mac to a 4K television.