IPv4 exhaustion
The 32-bit IPv4 address space has a hard ceiling of 4,294,967,296 addresses. IANA allocated its last unreserved /8 on February 3, 2011.
85.86%
of IPv4 space allocated
Allocated
3,687.45M
3,687,451,632
Unallocated / reserved
607.52M
607,515,664
Total IPv4
4,294.97M
232
By Regional Internet Registry
Timeline
- 1981 — IPv4 defined in RFC 791.
- 1993 — Classful addressing replaced with CIDR (RFC 1519) to slow exhaustion.
- Feb 2011 — IANA allocates the last /8 to APNIC. Top-level free pool exhausted.
- Apr 2011 — APNIC enters "last /8" policy (1 /22 per LIR).
- Sep 2012 — RIPE NCC enters last /8 policy.
- Jun 2014 — LACNIC free pool exhausted.
- Sep 2015 — ARIN free pool exhausted.
- Nov 2019 — RIPE NCC runs out (single /22 allocations only from waitlist).
- Ongoing — All new allocations come from returns, transfers, or waitlists. Secondary market prices ~$25–50/IP.