How Long Should You Warm Up?

Warm up phase, how long should it usually be? Is this something that we can be more flexible with? Or should we, like I said, a stopwatch that we're going to warm up for this certain amount of time? There is no set time. It will always depend on how you're feeling on the day. And there's almost, for me, there's almost like a meditation aspect to a good warm up where I really try and get into mind body awareness.