On this pageWhy IPv6 is not working on IPv4-only targets
If IPv6 is not working against a site, the usual reason is the site itself: an IPv6 proxy reaches hosts that publish an IPv6 address, plus supported CDN-fronted sites, and a large share of the web is still IPv4-only. When a target has no IPv6 route, the request fails; that is why a site that will not load over an IPv6 proxy is almost always a destination problem, not a proxy problem. The single most important step before buying Residential IPv6 or Datacenter IPv6 is to check your target: it should publish IPv6 addresses or be served by a supported CDN. Test it first with the IPv6 Checker; if you are still unsure, test on the shortest paid billing window (hourly for Residential IPv6, daily for Datacenter IPv6). Also read What is an IPv6 proxy? for the concepts behind this page.
Why IPv6 is not working on IPv4-only targets
For an ordinary IPv6 client, a host is reachable over IPv6 only if its DNS publishes an AAAA record. Many sites publish only an A (IPv4) record and no AAAA, which means there is no IPv6 route to them; an IPv6-only proxy has nowhere to connect, and the request fails. This is a property of the target, not a fault of the proxy: the same proxy that fails on an IPv4-only site works perfectly on an IPv6-enabled one.
IPv6 proxies do not silently fall back to IPv4 for you. If the destination has no AAAA record, the connection cannot complete over an IPv6 exit; the one exception is supported CDN-fronted domains, covered in CDN-aware IPv6 routing below. Check the target before committing a plan to it, and if you are unsure, test on the shortest paid billing window.
Check the target first
Run your real target host through the IPv6 Checker before you buy. It shows whether the hostname publishes IPv6 addresses (AAAA records) and whether its DNS points to a recognised CDN. If it publishes IPv6 addresses, an IPv6 plan fits. If it does not but a CDN serves it, read CDN-aware IPv6 routing below: a recognised CDN is not always a supported one, so test on the shortest paid billing window (hourly for Residential IPv6, daily for Datacenter IPv6). If it has neither, pick a Residential IPv4 plan instead.
You can also confirm an exit over IPv6 from code once you have a proxy. Use a host that you have verified is IPv6-enabled, and an IPv6-aware echo endpoint:
# Route through an IPv6 proxy to a verified IPv6-enabled echo endpoint
curl -x "http://USERNAME:PASSWORD@gw-2312.coldproxy.com:30000" https://api6.vipv6proxy.com/api/checker/my-ipimport requests
proxy = "http://USERNAME:PASSWORD@gw-2312.coldproxy.com:30000"
proxies = {"http": proxy, "https": proxy}
# This endpoint returns an IPv6 address only when an IPv6 path exists
print(requests.get("https://api6.vipv6proxy.com/api/checker/my-ip", proxies=proxies, timeout=30).json()["ip"])Dual-family detection needs IPv6-specific hostnames. A single hostname cannot reliably force both families, so use an explicitly IPv6 endpoint when you want to prove the IPv6 path.
Confirmed IPv6-compatible platforms
These major platforms publish IPv6 and work with ColdProxy IPv6 proxies:
- YouTube
- Bing
- Yahoo
- Netflix
For any host not on this list, treat IPv6 support as unknown: check it with the IPv6 Checker before you buy, and if you are still unsure, test on the shortest paid billing window.
CDN-aware IPv6 routing
A growing share of traffic terminates at a CDN, and major CDNs serve content over IPv6. ColdProxy IPv6 plans include CDN-aware IPv6 reachability (example CDNs: Cloudflare, Akamai, Fastly, and Amazon CloudFront, not the full supported set): for supported CDN-fronted domains that publish no AAAA record of their own, ColdProxy's CDN-aware reachability keeps supported requests on IPv6, with no IPv4 fallback. This applies equally to Datacenter IPv6 and Residential IPv6.
CDN-aware routing covers supported CDN-fronted domains; for everything else, reachability still depends on the target's own AAAA record. When in doubt, check the exact host you target with the IPv6 Checker, then test on the shortest paid billing window.
When to choose Residential IPv4 instead
Choose a Residential IPv4 plan when your targets neither publish IPv6 addresses nor sit behind a supported CDN, when a paid IPv6 test on the target fails, or when you need broad country coverage:
- Residential IPv4 (Unmetered) — Mbps speed-tier plan with 195+ country geo-targeting, billed hourly, daily, weekly, or monthly.
- Residential IPv4 (GB Based) — monthly traffic packs across 195+ countries when you prefer to pay for the bandwidth you use.
Residential IPv6 is USA-only and includes a /32 subnet; Datacenter IPv6 covers 25 countries and 47 locations (with an "All Country" random option) and ships a private /48 per location. If your workload needs a country IPv6 does not cover, Residential IPv4 is the right call.
The decision order is simple: check the target with the IPv6 Checker first. If it publishes IPv6 addresses or is served by a supported CDN, and it is in coverage, IPv6 is a cost-effective choice. If not, use Residential IPv4. If you are unsure, test on the shortest paid billing window. Compare options on /pricing/.
