Is tipping with the intent that it is zakat acceptable in Islam. For example tipping a waiter in a restaurant or in a hotel or a taxi driver.
First thing first.
Zakat is highly preferred to be given to Muslims, than to the non Muslims.
Next, talking about the poor, first priority is to be given to the poor who do not ask, and then to the poor who ask.
And finally make sure you abide by this verse...
And give to the kindred his due and to the Miskin (poor) and to the wayfarer. But spend not wastefully (your wealth) in the manner of a spendthrift . (Qur'an 17:26)
So, you would like to consider all the above factors, before you think of tipping.
Support: Who is zakat given to?
May the creator guide us all.