How do you know if your ph balance is good?

If you're healthy...: If you're healthy, your ph is good. Even if you're sick (unless you have ketosis), more than likely your ph is good. The body does everything it can to keep ph in a very tight range, say 7.35-7.45. It doesn't like any value outside that range. Even 7.30 is considered quite acidotic (like lemon juice) while 7.50 is quite basic (like lye). Focus on healthy eating to make it easier for body to keep.