IPv4 vs IPv6 Proxies: Differences and Which to Buy

On proxy marketplaces you'll see IPv6 proxies at very low prices, with promises of "millions of IPs". Tempting — but IPv6 has limits sellers rarely spell out: some sites can't be reached at all, and "a million IPs" may count as one. This guide explains how IPv4 and IPv6 differ, why IPv6 proxies are cheap, when they're still worth it, and how to check your proxy.

IPv4 and IPv6 in one minute

IPv4 addresses are 32 bits, like 203.0.113.25. There are only about 4.3 billion of them, and the registries ran out of new ones years ago. Because they're scarce, every IPv4 address has value — and a history.
IPv6 addresses are 128 bits, like 2001:db8:85a3::8a2e:370:7334. There are so many that one ordinary /64 range — the size a home network or a server is typically given — holds about 18 quintillion addresses.

The two protocols run side by side but don't talk to each other directly: an IPv4-only site can't be reached from an IPv6-only connection.

Why IPv6 proxies are cheap

Because IPv6 addresses are practically unlimited. A rented server can get a whole IPv6 range and spin up "millions of proxies" from it for next to nothing. Every IPv4 address, on the other hand, has to be bought or leased, so IPv4 proxies always cost more.

In other words, cheap IPv6 proxies are cheap because addresses are no longer scarce — not because of quality or trust.

The limits of IPv6 proxies

Many sites don't support IPv6 yet. If a domain has no AAAA record, an IPv6-only proxy can't connect. Plenty of big sites support it, but many small and mid-sized sites, APIs and older systems don't.
Sites block and rate-limit by range, not by address. Since one person can own a whole /64, many anti-abuse systems treat that range as one "user". A million IPs in one /64 may count as just one.
Server IPv6 is still a server IP. A hosting provider's IPv6 range still belongs to a hosting ASN, so it's treated like a datacenter proxy.
Reputation is per range. One careless customer can get a whole range flagged, along with every "IP" in it.

When IPv6 proxies are still worth it

The target supports IPv6 and you've checked it accepts traffic from your range.
Your job needs a great many addresses and the site limits per address, not per range.
You're testing IPv6 connectivity on your own systems.
The budget is tight and the job doesn't need high trust.

For social media accounts, ads or sites with anti-fraud systems, cheap IPv6 proxies usually aren't a good choice.

Comparison table

Criterion	IPv4 proxy	IPv6 proxy
Price	Higher (scarce addresses)	Very low
Sites you can reach	Almost all	Only IPv6-enabled sites
Number of IPs	Limited	Practically unlimited
How sites block	Per IP	Often per range
Good for	Most jobs	High-volume work on IPv6 sites

Check your proxy and the target

See whether the proxy goes out on IPv4 or IPv6:

Terminal

# Returns IPv4 only (fails if the proxy has no IPv4)
curl -s -m 15 -x "http://USER:PASS@HOST:PORT" https://api.ipify.org

# Returns IPv6 if the proxy goes out on IPv6, otherwise IPv4
curl -s -m 15 -x "http://USER:PASS@HOST:PORT" https://api64.ipify.org

See whether the target supports IPv6 (an AAAA record means yes):

Terminal

nslookup -type=AAAA example.com

The other general checks are in how to check a proxy.

4G proxies and IPv6

Many mobile carriers give phones IPv6 while still providing IPv4 through the carrier's NAT. Whether a 4G proxy goes out on IPv4 or IPv6 depends on how the provider sets it up — ask the seller or check with the two commands above.

The difference that matters more isn't the IP version but the IP's source: mobile-carrier IPs are shared by many real subscribers, so sites can't block them without blocking their own customers. Cheap IPv6 is the opposite: one range on a server, easy to block as a whole. The full comparison of IP sources is in 4G vs residential vs datacenter proxies.

65Proxy

We don't sell "millions of IPs" of server IPv6. 65Proxy sells 4G proxies on Singapore mobile-carrier IPs, rotated on demand by link or API (at most once every 5 minutes), 200GB per plan, priced 1 day $4, 7 days $13, 1 month $40. You can run the checks above straight away on the shortest plan. See pricing.

Frequently asked questions

The big platforms support IPv6, but cheap IPv6 proxies are usually server ranges that get recognised and limited as a whole. For important accounts, mobile or residential IPs are more reliable. See proxies for Facebook.

Why can't my IPv6 proxy open some sites?

Almost certainly because the site has no IPv6 yet (no AAAA record). An IPv6-only connection can't reach an IPv4-only site.

Are "1 million IPv6 IPs" real?

In number, yes — a single /64 is far bigger than that. But because sites often group the whole range, a million addresses in one range aren't worth a million independent IPs.