Unlocking iphone 4 via jailbreak?

Is there any jailbreak out for ios 7.1 that can unlock my iPhone 4 or enable it to use any carrier for free? If anybody could point me in the right direction or knows if it is possible to do this I would really appreciate if you took the time to help.<3

Added (1). i want to do this for free if possible

Why not get the phone factory unlocked? No need to jailbreak the phone, just unlocks the phone. If you need help with getting the phone factory unlocked, mail me for references.

Free stuff often lacks quality.So don't prefer free codes for unlocking your mobile. You need to unlock
your mobile according to the network you reside right? Its a paid service. First find out your mobile phone IMEI number. You can find this by typing in *#06# and then hitting the enter o rsend key on your Iphone. This number is completely unique to your phone and will be used to generate or calculate an unlock code for your mobile. Then the unlock code here http://www.unlock-zone.com/apple-iphone-4/rs5wp9/
unlock code specified in it you can proceed unlocking your mobile.Once you have your iphone unlock code, you can follow this simple steps in this site http://www.mobileunlockguide.com/apple-iphone-4 below to full unlock your mobile without vain