IPv4 and IPv6 are two versions of the addressing system that lets devices find each other on the internet. IPv4 uses short 32-bit addresses, and there are too few of them. IPv6 uses 128-bit addresses and has room for effectively every device. For a website owner, the practical answer in 2026 is simple: keep IPv4 working, add IPv6 next to it, and do not switch one off for the other.
Below we cover how the two differ, whether IPv6 really is faster, what it means for security, and what to check with your hosting provider.
TL;DR
- IPv4 (32-bit, like
203.0.113.10) is still required. A large part of the internet cannot be reached over IPv6 alone. - IPv6 (128-bit, like
2001:db8::10) removes the address shortage and the need for NAT, and is now used by roughly 64% of US users. - IPv6 can be faster, but part of the gain is a browser trick, not magic. Expect small differences, not a rebuilt site.
- The recommended approach for hosting is dual-stack: both protocols at once.
- Your firewall rules and monitoring must be checked for IPv6 explicitly. They do not carry over automatically.
Table of Contents
- The core difference in one table
- Why there are two versions at all
- Where adoption stands in the US
- Is IPv6 faster?
- Security: no, IPv6 is not automatically safer
- Dual-stack: the sensible default
- What this means by site type
- DNS: A and AAAA records
- How to check your site
- What to ask your hosting provider
- Our perspective
- Hosting that handles the setup for you
- FAQ
- Sources
The core difference in one table
| IPv4 | IPv6 | |
|---|---|---|
| Address length | 32 bits | 128 bits |
| Written as | Four numbers, 198.51.100.7 | Eight hex groups, 2001:db8:85a3::8a2e:370:7334 |
| Address supply | Exhausted at the registry level | Effectively unlimited |
| NAT needed | Usually yes | No, in most deployments |
| Header | 20 bytes, variable | 40 bytes, fixed layout |
| Readability | Easy to remember and type | Hard to remember, easy to mistype |
| Support | Universal | Very wide, not universal |
The header detail surprises people. IPv6 packets carry a larger fixed header, but the layout is simpler, so routers handle it with less work. The size of the address, not the header, is what changes your daily life.
Why there are two versions at all
IPv4 was designed when a few million addresses looked like plenty. With 32 bits you get about 4.3 billion addresses, and phones, laptops, TVs, cameras and servers used them up. The regional registries ran out of free space years ago. The American registry, ARIN, now works through a waiting list and a transfer market, and hands out only small recovered blocks. In the first half of 2026 secondary-market addresses sold for around $20 each according to one summary of registry data, so a single address is not free money, but it is a real line item.
The internet stretched IPv4 with NAT (network address translation). Many devices share one public address, and a router keeps a table of who asked for what. It worked, but it has costs. ARIN's network architects point out that NAT creates choke points and single points of failure, and that the case for IPv6 is now as much about simpler network design as about running out of addresses.
IPv6 was built to end that. Every device can have its own public address, so connections can run end to end without translation.
Where adoption stands in the US
IPv6 is no longer a niche. As of August 2026, the regional registries' adoption data puts the United States at about 63.6%. Globally, Google traffic passed 50% IPv6 in spring 2026.
Those numbers measure different things (users capable of IPv6 versus share of traffic to one company), so do not compare them directly. The message is the same: about half or more of your visitors can reach you over IPv6 if your site offers it. Mobile networks lead. Home and office equipment trails, and ARIN notes that consumer electronics and IoT devices other than phones often have poor IPv6 support.
That gap is why the other half of your visitors, and many older office networks and legacy services, still need IPv4.
Is IPv6 faster?
Sometimes, a little. There are two separate reasons.
Fewer hops. Measurements show the average path between networks is around 5.7 hops on IPv4 and 4.7 on IPv6. Fewer hops usually means lower latency, and skipping NAT removes a translation step.
A head start in the browser. Many operating systems and browsers use an algorithm called Happy Eyeballs, which tries IPv6 first. According to Cloudflare, some of them delay IPv4 attempts by 25 to 300 milliseconds. Part of the speed you see is that built-in preference, not the protocol being inherently quicker.
Cloudflare has reported gains of up to 27% on some page loads and 10 to 40% on certain mobile connections. Treat those as best cases from a very large network. On your own site, the biggest speed factors remain server response time, caching, image weight and the HTTP protocol version. If you are tuning those, our guides on website performance metrics for small businesses and HTTP/2 in hosting will move the needle more than the IP version will. For how load time connects to rankings, this overview of page speed and SEO is a good next step.
Does the IP version affect SEO?
Not directly, as far as we can document. Search engines crawl over both. What matters is that your site answers reliably and quickly on whichever one the visitor or crawler uses. A broken IPv6 record that times out is worse than having none, because clients may wait before falling back to IPv4.
Security: no, IPv6 is not automatically safer
Two myths come up constantly.
"IPv6 has built-in security." IPsec support was once mandatory in the original design, but that did not make IPv6 networks secure by default. What you run on top of it, and how you configure it, decides your risk.
"NAT is a firewall." It is not. NAT hides internal addresses as a side effect, but a stateful firewall does the real protecting. ARIN's authors describe the security-through-obscurity belief around NAT as a myth. With IPv6 and end-to-end addressing, firewall policy has to be explicit.
The practical warning comes from NIST: do not assume your IPv4 security controls understand IPv6. Existing firewalls and intrusion detection may not inspect IPv6 traffic unless configured to. If you manage your own server, a common mistake is locking down IPv4 carefully and leaving IPv6 wide open because nobody wrote rules for it.
If you run a VPS or dedicated server, check these:
- Your firewall (iptables, nftables, ufw or a cloud firewall) has IPv6 rules that mirror the IPv4 ones.
- Services bound to
0.0.0.0are also deliberately handled on::. - Fail2ban, log monitoring and rate limiting see IPv6 client addresses.
- Your admin panels and SSH are restricted on both protocols.
On managed shared or WordPress hosting, the provider handles the server side, but you should still ask the questions in the checklist below.
Dual-stack: the sensible default
The IETF's guidance on transition mechanisms, RFC 6180, recommends dual-stack for most enterprise and hosting environments. Both protocols run side by side, "ships in the night", so each client uses whichever it can. This avoids tunneling and MTU headaches, and it lets you move application by application.
Going IPv6-only too early can cut off visitors and services that are still IPv4-only. ARIN does lay out a business case for IPv6-only enterprise networks, because maintaining two stacks costs staff time. That argument fits large organizations with their own address pools and engineers. A small business website is the opposite case: the extra effort of dual-stack is tiny, and the cost of missing visitors is real.
For an enterprise-wide view, RFC 7381 covers IPv6 deployment guidelines for network administrators.
What this means by site type
Small business site or blog on shared hosting. You do not choose. Your host assigns addresses and you point your domain at them. Your job is to confirm that the site answers on both IPv4 and IPv6, and that your DNS is set up correctly.
WordPress store or membership site. Same as above, with extra care for anything that checks visitor IPs: security plugins, rate limiters, payment fraud rules, geolocation. Plugins that store or compare IPv4 addresses only can misbehave with IPv6 visitors. Test checkout and login from an IPv6 connection.
Agencies and resellers. You will field client questions about this. Make sure each client domain has both record types, and that your own tooling handles IPv6 in logs and allowlists.
VPS and dedicated server owners. You control the stack. Enable IPv6 on the interface, add firewall rules, and update reverse DNS and mail settings. Mail is the sensitive part: mail servers sending over IPv6 need proper reverse DNS and authentication records, or messages get rejected.
DNS: A and AAAA records
DNS is where the two protocols meet your domain. An A record maps your domain to an IPv4 address. An AAAA record maps it to an IPv6 address. Publish both, and clients pick one.
Common pitfalls:
- An AAAA record pointing to a server that is not actually listening on IPv6. Visitors on IPv6 get errors or slow fallbacks.
- Forgetting to update the AAAA record after a server move. The old address keeps serving stale content.
- Mismatched TLS certificates or virtual host settings on the IPv6 address.
If you want more background on how DNS behaves and affects speed, see our DNS hosting guide. If you are moving servers, the AAAA record is exactly the kind of detail that slips through, so include it in your website migration checklist.
How to check your site
- Look up your records. Run
dig A yourdomain.comanddig AAAA yourdomain.com, or use any DNS lookup tool. You want an answer to both, or a clear reason why not. - Test from an IPv6 connection. Many mobile hotspots are IPv6-capable. Load the home page, log in, and complete a checkout or form.
- Request over IPv6 explicitly. With curl,
curl -6 -I https://yourdomain.comforces IPv6. A normal response with a valid certificate is what you want. - Check email. Send a test to an outside mailbox and read the headers for SPF, DKIM and DMARC results.
- Review logs. Confirm that your analytics, firewall and security plugins record IPv6 visitors properly.
What to ask your hosting provider
Before you sign up, or when you review your current plan, ask:
- Is IPv6 available on my plan, and is it enabled by default or on request?
- Do you run dual-stack, and can I get both A and AAAA records?
- On a VPS or dedicated server, do I get an IPv6 block, and what size?
- Does the firewall or security layer you manage cover IPv6 traffic?
- If I move servers, who updates records and tests both protocols?
The last question matters more than it looks. A migration that forgets IPv6 is a classic cause of intermittent, hard-to-reproduce errors. Our guides on what website migration involves and how to move a small business site walk through testing before you switch DNS.
Our perspective
We look at this from the operations side, where the question is rarely "which protocol is better" and almost always "what breaks for a real visitor." Our sites are run by SRE and DevOps engineers in the EU and US, and the lesson from that work is consistent: protocols are easy to enable and hard to verify. The failures we see in the wild are half-finished setups, such as an AAAA record with nothing behind it, or a firewall that only knows IPv4.
So our advice to site owners is boring on purpose. Keep IPv4 until your analytics show IPv4 visitors are negligible, which for most businesses will be a long time. Add IPv6 where your host supports it, test it from outside your own network, and treat firewall and monitoring coverage as part of the job, not an afterthought. Do not chase a speed claim: the gains are real on some paths but small next to caching, a good server and a lean page.
And whichever protocol your visitors use, you want a host that tells you plainly what is configured, backs up your site daily, and does not leave you guessing.
— Ihor
Hosting that handles the setup for you
If you would rather not hand-edit DNS and firewall rules, a managed plan removes most of that work. Our WordPress hosting suits sites that need caching and managed security out of the box, and shared hosting covers smaller sites. If you want full control of the network stack, including your own firewall rules, look at our VPS hosting. Every plan comes with a 30-day money-back guarantee and free migration, so you can move an existing site and check it on both protocols before committing. You can start with the free migration service.
FAQ
Should I use IPv4 or IPv6?
Use both. IPv4 still reaches everyone, and IPv6 reaches the large and growing share of users on modern networks. Running dual-stack is the approach the IETF recommends for hosting environments.
Does IPv6 make the internet faster?
Sometimes. Paths average fewer hops and avoid NAT, and browsers prefer IPv6 by design, so some connections load faster, especially on mobile. The difference is usually modest, and it will not fix a slow server or heavy pages.
Why do people still prefer IPv4?
Familiarity and compatibility. IPv4 addresses are short and easy to read, tools and plugins have supported them for decades, and many legacy devices and services handle nothing else. Mistyping a long IPv6 address is also much easier.
Should I use IPv6 at home?
If your internet provider and router support it, leaving it on is fine, and most devices will use it automatically. Check that your router's firewall covers IPv6 too, because IPv4 protections do not always carry over. If you hit odd connection problems with a specific app, your provider's support can help before you disable anything.
Do I need to change anything on my website?
Often nothing, if your host handles dual-stack. Confirm that your domain has both A and AAAA records, test the site over IPv6, and make sure any security plugins handle IPv6 visitor addresses.
Sources
- RIR IPv6 adoption data by economy, August 2026 (APNIC/NRO)
- Google hits 50% IPv6, APNIC Blog
- The Business Case for IPv6-Only Enterprise, ARIN
- The Business Case for IPv6: Recovering and Monetizing IPv4 Addresses, ARIN
- IPv4 address exhaustion overview
- 98.01% of sites on Cloudflare now use IPv6, Cloudflare Blog
- Cloudflare Passes 10,000 Connected Networks, Cloudflare Blog
- RFC 6180: Guidelines for Using IPv6 Transition Mechanisms
- RFC 7381: Enterprise IPv6 Deployment Guidelines
- NIST ITL Bulletin on IPv6 security
- Page speed and SEO