You can check if your Netflix stream is actually 4K - here's how

You might pay the premium price to subscribe to Netflix's 4K-capable plan, but are you actually streaming content in 4K ...
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How to Stream HBO Max Movies and Shows in 4K If You Aren't Already

Basic with Ads - $9.99/month (No 4K) Standard - $16.99/month (No 4K) Premium - $20.99/month (Includes 4K) If you’d like to check whether your current equipment is up to the task, Max has a list of ...