IPv4 vs IPv6 Proxies

The difference is the address format the proxy sends your requests from. Everything else, such as the protocol, the rotation and the IP type, is a separate choice.

An IPv4 proxy is a proxy whose outgoing address is an IPv4 address, the format defined in RFC 791 in 1981: four numbers from 0 to 255, 32 bits in all. It works like any proxy. Your app connects to the proxy's host and port, the proxy opens a connection to the site from its own IPv4 address, and the site sees that address instead of yours.

Because 32 bits allow only about 4.3 billion addresses, IPv4 ran short long ago. ARIN, the registry for North America, depleted its free pool on 24 September 2015 (ARIN), and the RIPE NCC, which serves Europe, the Middle East and parts of Central Asia, exhausted its pool in November 2019 (RIPE NCC). New IPv4 addresses are now obtained through transfers and leases. That scarcity is what makes each IPv4 address carry weight: a site can block one without hurting many other people, and a provider cannot hand out endless fresh ones.

An IPv6 proxy sends your requests from an IPv6 address. RFC 8200, the current IPv6 standard (2017), raises the address size "from 32 bits to 128 bits". Most IPv6 networks are split into /64 subnets, because the last 64 bits of an address identify the interface (RFC 4291), and end sites such as homes and businesses usually receive a /48 or /56 (RFC 6177).

A provider with one /48 block therefore has more addresses than the whole IPv4 internet. That is the appeal of IPv6 proxies: a new address for every request costs almost nothing. It is also the catch, as the next sections show.

A site supports IPv6 when its domain has an AAAA record in DNS. If it has none, an IPv6-only proxy cannot reach it at all. We looked up the A (IPv4) and AAAA (IPv6) records of 36 sites that scrapers often target on 23 October 2026, for the bare domain and its www host, from one resolver on one day. Google-owned sites were not tested.

All 36 sites answer over IPv4. Most of the large retail, travel, jobs and real-estate sites that scrapers and price monitors work on had no IPv6 address at all. Records change, so check your own targets before you buy: dig AAAA example.com on macOS or Linux, or nslookup -type=AAAA example.com on Windows, shows whether a host has an IPv6 address.

Two details matter when you read such a check. A site may publish IPv6 on www but not on the bare domain, or the other way round, as Amazon and Reddit did. And a site behind Cloudflare can accept IPv6 even if its own servers do not: Cloudflare "enables IPv6 on all domains" by default and generates the AAAA records itself, but Enterprise customers can turn the setting off, and it does not apply to the bare domain on partial or hosting-partner setups (Cloudflare: IPv6 compatibility). Three sites in our check whose IPv4 addresses are in Cloudflare's ranges, Discord, Indeed and X, had no AAAA record.

On sites that support IPv6, they are blocked in bigger pieces. A household or a server normally gets a whole /64 or more, so sites treat the /64 as one user. Wikipedia's guidance for its administrators says a single user "will generally use the same /64 range" (Wikipedia: Blocking IP addresses). When a site limits or blocks a /64, every address in it, all 2⁶⁴ of them, is blocked at once.

That is why millions of IPv6 addresses do not add up to millions of identities. If a provider's addresses sit in a few blocks registered to a hosting company, a site sees a few datacenter networks, however many addresses you rotate through. IPv4 residential and mobile proxies spread requests across many networks and providers instead, which is what spreads the load in the site's eyes. How a given site scores IPv6 traffic is not public, so test on your own target.

They can connect to sites that leave Cloudflare's IPv6 setting on, which is the default, as shown above. Whether a request then passes depends on the site's own Cloudflare settings and bot rules, which look at much more than the IP version: the network the address belongs to, its history, the browser fingerprint and the request rate. A datacenter IPv6 block meets the same scrutiny as a datacenter IPv4 range. If you see 403 errors, the causes and fixes are in Cloudflare 403 Forbidden.

Because IPv4 reaches every site and IPv6 does not. APNIC's measurement puts the share of internet users who can use IPv6 at 43.64% worldwide, 51.28% in the Americas and 37.37% in Europe (30-day average to 22 October 2026, APNIC IPv6 capability). Users' devices have moved faster than websites: many of the sites in our check, including most large retailers, have not published IPv6 at all.

The two protocols cannot talk to each other directly either. A device or proxy that has only IPv6 needs a translator, such as NAT64 (RFC 6146), to reach an IPv4-only site, and then the site sees the translator's IPv4 address, not the IPv6 one you paid for. Networks that support both protocols run them side by side, which is called dual-stack.

Use IPv4 unless you have checked that your targets support IPv6 and accept traffic from the provider's networks.

• Scraping, price monitoring, SEO and SERP checks: IPv4 rotating residential proxies. They reach every site and spread requests across many networks; see proxies for web scraping.
• Social media and account management: IPv4 residential, mobile or static ISP IPs, one per account.
• A large volume of requests to one IPv6-ready target that tolerates datacenter traffic: IPv6 proxies can be the low-cost option, after a test.
• Testing how your own site or app behaves over IPv6: an IPv6 address from your own network or host, not a proxy.

Yes, as far as the provider holds blocks in the places you want. Websites locate an IPv6 address the same way as an IPv4 one, from IP geolocation databases and registry data, so the location you see depends on where the block is registered and announced. Providers with a few large blocks offer fewer locations than residential IPv4 pools; ProxyField's residential pool has 412M+ IPs in 195+ countries, with targeting by country, region (state) and city.

An IPv6 proxy is set up like any other: host, port, username and password. Three details differ:

For SOCKS, note that SOCKS5 can carry IPv6 addresses (RFC 1928) and SOCKS4 cannot; see SOCKS4 vs SOCKS5. Setup for IPv4 proxies in common tools is in how to set up a proxy.

• RFC 791, Internet Protocol (1981); RFC 8200, IPv6 Specification (2017); RFC 4291, IPv6 Addressing Architecture; RFC 6177, IPv6 Address Assignment to End Sites; RFC 6146, NAT64; RFC 3986, URI syntax; RFC 1928, SOCKS5
• ARIN: IPv4 free pool depletion and RIPE NCC: IPv4 run-out
• APNIC IPv6 capability, world
• Cloudflare: IPv6 compatibility (last updated 25 August 2026)
• Wikipedia: Blocking IP addresses
• ProxyField DNS check of 36 sites, 23 October 2026: A and AAAA lookups for each domain and its www host