Factory Reset Your Iphone without Password 
1.iTunes Installed on your PC.
2.USB Cable

Once you are ready with above mentioned things, we are ready to proceed. This Factory reset without password Method works on all iphones 6/5s/5c/5/4s/4/3gs/iPad or iPod.

Step 1: First of all we will power off the phone. What we will do is keep holding Sleep/wake Button and Slide to Power off.

Step 2: Now you need to start iTunes on your Computer and make sure USB Cable is attached to it. Now Hold Home Button and then insert USB data Cable into your iphone.

Step 3: You will be presented with Connect to iTunes screen on your iphone. Now you can Release the Home Button. iTunes on your Computer should Detect the iphone in Recovery Mode. You could see something like below Picture on your PC.

Step 4: Basically what it says is to reset the Software to Factory standard. So Now go ahead and Click on Restore then Restore and Update. This will delete Everything from your phone so Caution there. Though to Factory Reset iphone without Password you can afford to loose data but will want to have access to your phone again right ?

Step 5: iTunes will extract the software and you can see the progress bar as well. Now just sit back and relax and wait for the software to do all the Process for you.

Step 6: Once extracting completes, You can see Apple logo on the screen it will then begin installing on your phone.

Step 7: Once the phone is restored you can start all over again like how the phone comes out of the box when its new. It is safe now to remove the USB Cable. You will be asked to Select Language, Country/Region, Wifi password and few other things.

You would be now able to Create new Passcode for your iphone without any trouble. So this is how you Factory Reset any iphone without password using iTunes. The method will delete everything from the phone but you will be now able to access it with entering the old password and creating the new one which you can remember easily this time.