I can't connect to my Wi-Fi?

My iPhone 4 (which is on ios 6) will not connect to my home Wi-Fi. I made sure that the SSID and password were correct multiple times. None of our phones will, I don't know what to do.

Have your try to login to your Wi-Fi and try several suggestion below:
1. Have your try to login to your Wi-Fi and change the channel to automatic (let say the previous one is channel 1 or 6 or 11) can you try to make it automatic (let the Wi-Fi decide which channel is the best)
2. Try to remove your security password from your Wi-Fi and try to connect your iphone with Wi-Fi (with no security)
3. If it can connect then try to put security back with WEP securiy type, and again try to connect your Wi-Fi from your iphone (this security type is less secure)
4. If it can connect then try to change the security to WPA / WPA2 with PSK and try to connect it again (this security type is more secure than WEP)

Hope this can help you out

I had a similar problem 2 years ago with my cell phone,.
Change the password on the Wi-Fi router by logging into the Wi-Fi control panel. Try some thing simple with all lower case letters. I had an issue with one or two characters that were in the wrong case.
Your phone should see the router name( SSID) . You may have to remove the current instance of this Wi-Fi connection on your phone first so it won't try to connect with the original password.
If you are unsure how to get to the router control panel, check the manula or google the router name and model number along with "control panel"