GLOSSARY

IPv4 vs IPv6: what is the difference?

IPv4 uses 32-bit addresses and is running out; IPv6 uses 128-bit and is effectively unlimited. Learn the difference and see your IP free.

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IPv4 and IPv6 are the two versions of the Internet Protocol addressing scheme. IPv4 is the original 32-bit system we are running out of; IPv6 is its 128-bit successor with an effectively unlimited address space.

Address size and format

IPv4 addresses are four numbers like 93.184.216.34 — about 4.3 billion total, now exhausted. IPv6 addresses are eight groups of hex like 2001:0db8:85a3::8a2e:0370:7334 — 340 undecillion of them, so every device can have its own without NAT.

Why the transition is slow

IPv4 and IPv6 are not directly interoperable, so the internet runs both in parallel (dual-stack) during a long transition. Techniques like NAT stretched IPv4’s life, which is part of why IPv6 adoption, while growing, has taken years.

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FAQ

Do I have both an IPv4 and IPv6 address?›
Often yes — many connections are dual-stack. Our tool shows the address your request arrived on.
Is IPv6 more secure?›
Not inherently. It removes the need for NAT and has huge address space, but security depends on configuration, not the version.

Related

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