IP address converter
Type an address in any common form: dotted IPv4, a decimal number, 0x hex, binary, or IPv6. The tool recognises it and shows every other form, including the shortest IPv6 spelling from RFC 5952 and the reverse DNS name.
Runs in your browser: nothing you enter is sent anywhere.
How to use it
- Type or paste an address or number.
- The tool detects the format from its shape and fills in the other forms.
- Press Copy next to the one you need.
How it works
IPv4 addresses are handled as unsigned 32-bit numbers and IPv6 addresses as 128-bit numbers, so conversion between forms is exact. The hex form is padded to 8 digits, the binary form shows the four octets with 8 bits each, and the IPv4-mapped form is ::ffff: followed by the dotted address. For IPv6, the compressed form follows RFC 5952 and the expanded form shows all eight groups of four digits.
Example
192.168.1.1 is 3232235777 in decimal, 0xC0A80101 in hex and 11000000.10101000.00000001.00000001 in binary. The IPv6 address 2001:0db8:0000:0000:0001:0000:0000:0001 has two runs of two zero groups; the first is replaced, giving 2001:db8::1:0:0:1.
Tips
- Leading zeros in a dotted address are read as decimal, not octal (010.0.0.1 is 10.0.0.1).
- For network, mask and host range, use the IP subnet calculator.
Frequently asked questions
How is an IPv4 address turned into a single number?
The four parts are the bytes of a 32-bit number, so a.b.c.d equals a × 16,777,216 + b × 65,536 + c × 256 + d. For 192.168.1.1 that is 3,232,235,777, which is C0A80101 in hex.
What is the RFC 5952 form of an IPv6 address?
It is the one recommended short spelling: lowercase hex, no leading zeros in a group, and the longest run of two or more zero groups replaced by ::. If two runs tie, the first is replaced. A single zero group is written 0, never ::.
Which formats can I type in?
Dotted IPv4 (192.168.1.1), a plain decimal number, hex with 0x, binary with 0b, 32 binary digits or four binary octets separated by dots, and IPv6 in full or shortened form, optionally in square brackets or with an embedded IPv4 part such as ::ffff:192.0.2.1.
What are the reverse DNS names?
They are the names used for PTR lookups. For IPv4 the octets are reversed and followed by in-addr.arpa; for IPv6 each of the 32 hex digits is reversed and separated by dots, followed by ip6.arpa.
Is anything sent to a server?
No. All conversions are done in your browser.