doesn anyone know how much power(watt) stock speakers can handle?

Provide more info, then we will talk

im planning to amp my stock speakers and wanted to know how much watt they can handle

more than u think!!!

haha, what im thinking is very low. so must be higher

Just buy a good amp, if you plan in upgrading the speakers eventually.
 

The stock speakers won't take that much power, but they will appreciate CLEAN power. 99% of the time, and speaker is toasted because of distortion, not because of clean power.

Buy whatever amp will work well with future speakers. 50wx4 will power most speakers, but there are a few better speakers that like 100 watts. a 100wx4 amp might get expensive though.

If you block low frequencies, they can handle quite a bit...more
 

As stated below, good clean power is what is best for speakers. But it is also important not to ask them to reproduce frequencies they are not designed to handle. If you have 4" door speakers, and feed them full range, they are not going to last that long. Your 6.5" deck speakers may can probably handle a bit more bass. If you get a quality amp with a crossover you can experiment with how low they can play without distortion. Once they distort, you are on borrowed time. Good luck.

i dont know much about audio, wut if you got a radio with 50x4? do u still need an amp?

Amps built into head unit's are typically very weak.
 

Thought the head units are marketed at 50x4, what they don't tell you is that this is a peak power output, usually specified with a higher level of distortion (say, 1%). Those head units can not sustain 50 watts per channel, in fact they can usually not sustain more than 12 watts/channel (also known as RMS power).

A separate (good) amp like PPI, rated at 50x4 is almost always rated at continuous or RMS power...and usually at a much lower distortion. So a PPI amp may be rated at 50x4 RMS, 0.01% distortion. Good speakers will demand this kind of power.

So, if you want to compare apples to apples, you'll have to look at the specs on the headunit, and find the continuous or RMS power at the *same* distortion level as the quality amp.

In reality, you'll get much better performance out of external amps, compared with the small internal amps that are built into headunits. High end head units don't even provide internal amps, for several reasons...there isn't enough room to add the circuitry needed for a quality amp, a quality amp would generate too much heat, and squashing an amp and preamp into a tiny little box results in compromises to the sound quality yielded from both the pre-amp and amp sections of the head unit.

thanx Raj