IP address storing in MySQL database using PHP [duplicate]

This tutorial might help you.

The most efficient way of saving IPv4 addresses is with an INT field (not VARCHAR as you might expect). You convert them using PHP's ip2long and back using either MySQL's INET_NTOA function or PHP's long2ip function.

If you need to store IPv6, you'll want to use a BINARY field instead and PHP's inet_pton function.

you can store them in a binary field with a length of 128 bits (16 bytes, BINARY(16) or VARBINARY(16)). to convert any ip address to its binary representation, you can use the php function inet_pton. this method will work for both IPv4 and IPv6 addresses. inet_ntop can be used to get back the string representation of the stored ip address (regardless of version)

Generally you can go with VARCHAR(45) as it will be long enough to even store IPv6.