IP converter (IPv4 and IPv6)
Convert IPv4 addresses to decimal, hexadecimal and binary and back, expand and compress IPv6, generate the mapped IPv6 and see whether the IP is private, public or reserved.
IP to decimal, binary and IPv6
Everything happens on your device: nothing is uploaded to the internet.
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IP converter (IPv4 and IPv6): what it is for
Type an IPv4, an IPv6 or the decimal number of an address and see every representation: decimal, hexadecimal, binary, octal, mapped IPv6 and the reverse DNS name. For IPv6, the tool shows the RFC 5952 compressed form and the expanded form with all eight groups, plus the address type (private, public, loopback, link-local, CGNAT or multicast).
Nothing is sent to a server: the conversion happens in your browser.
How to use
- Type the address.
- See the conversions and the IP type.
- Copy the format you need.
When to use it
- Storing IPs as numbers in a database.
- Comparing IPv6 addresses written in different ways.
- Building reverse DNS zones.
Frequently asked questions
How does an IPv4 address become a decimal number?
Each of the four octets is a number from 0 to 255. The decimal is the first × 256³ + the second × 256² + the third × 256 + the fourth: 192.168.0.1 becomes 3,232,235,521.
What does expanding and compressing IPv6 mean?
The compressed form removes leading zeros and replaces the longest run of all-zero groups with ::. The expanded form shows all eight groups with four digits each, useful for comparing and sorting addresses.
How do I know if an IP is private?
The private IPv4 ranges are 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. In IPv6, addresses starting with fc or fd are unique local and those starting with fe80 are link-local.
Is it really free?
Yes, 100% free. No sign-up, no subscription and no usage limits. All Tools123 tools are free and run right in your browser.