Tipping is a simple subject: many establishments already incorporates a "Service Charge" (often designated sa "SC" on machine printed receipts) or you tip independently.  If you intend to tip, there isn't a X% that you multiply to your total bill.  Any amount up to PhP200.00 is good enough.  (Please note that as of this writing, the exchange rate is US$1.00=~PhP52.00.)

Some restaurants and bars do not already incorporate a service charge however. Tipping is usually expected, but don't feel pressured to leave a tip if the service wasn't good.

Usually 20-40 pesos is good for a restaurant if your bill was between 1000-1500 and there is a service charge. And between 50-100 if more than that but under 3,000. If higher than that and already has a service charge, tip no more than 150 or 200 even if the service is good. For those without Service charge and the service was really good give at least 3% of the bill with a minimum tip of 30 pesos. even without a service charge remember that 100 is a big tip already and keep in mind that these servers are not used to getting a service charge so they will appreciate whatever tip you give. (The current exchange rate is US$1 = 47.)