Factory reset iphone 4s without itunes- forgot passcode?

I forgot passcode to my iphone 4s. I can't restore or put it in recovery mode and restore with itunes because i no longer have the computer that i set my phone up in the first place. I have tried pretty much everything- i-funbox, gecko tool… Are there any other solutions?

So as long as you have a computer sign in to your apple account on it then put your phone in dfu mode (look it up on the Internet how to do it) then iTunes will say iPhone is in recovery mode you must restore and update it before you can use it then continue and it should work

Yea flubber is right. Put it in to recovery or dfu mode then factory reset it on your computer to have a "new" used iPhone 4s