IPv4 vs IPv6 Explained Without the Jargon

Every device connected to the internet has an IP address. It's the equivalent of a phone number, but for computers. There are two systems in use right now: IPv4 (the old one) and IPv6 (the replacement).

You probably don't notice which one your devices use day to day. But the choice affects which websites you can reach, how much your ISP charges (sometimes), and how easily someone can track your location.

The Phone Number Analogy

Think of IPv4 as the original 7-digit phone numbers we had decades ago. There were enough numbers when only some people had phones. As phones became universal, we ran out and added area codes. Then we added country codes. Eventually we needed an entirely new system.

IPv4 has the same problem at internet scale. The original system supports about 4.3 billion unique addresses. Sounds like a lot until you realize there are 5+ billion smartphones, plus laptops, smart TVs, refrigerators, security cameras, and IoT devices all wanting an address. We ran out of new IPv4 addresses around 2011.

IPv6 is the new system designed to never run out. It supports 340 undecillion addresses (3.4 followed by 38 zeros). Enough for every grain of sand on Earth to have its own internet address.

What This Looks Like

You can see your current IP addresses by checking WhatIsMyLocation. Some networks show only IPv4, some show only IPv6, some show both.

Why You Might Care

When you might see IPv6 in action

• Visiting modern websites (Google, Facebook, YouTube all support IPv6)
• Using a mobile carrier in the US (Verizon, T-Mobile push IPv6 by default)
• Connecting from newer routers (most made after 2018)

When you might still be on IPv4

• Home internet through older ISPs
• Corporate networks that haven't migrated
• Some VPN providers
• Many older smart-home devices

Why ISPs sometimes prefer IPv6

IPv4 addresses are now traded as a commodity. ISPs pay $20-50 per IPv4 address to lease blocks. IPv6 is free and abundant. New ISPs in growing markets often default to IPv6 because it's cheaper.

Privacy and Tracking Differences

This is where it gets interesting for non-technical users:

IPv4 with NAT (Network Address Translation): Your home router shares one public IPv4 address among all devices on your network. Websites can see your router's IP but not the individual device. Your phone, laptop, and smart TV all look the same.

IPv6 without NAT: Each device gets its own public IPv6 address. Websites can technically see and track each device individually. Some operating systems randomize the address regularly to prevent this.

For most people, IPv6 is slightly less private by default but slightly more performant. iOS and Android both implement privacy address rotation by default to mitigate the tracking concern.

What If a Website Doesn't Work?

A small percentage of websites in 2026 still don't support IPv6. If you're on an IPv6-only network and a site fails:

1. The browser usually falls back to IPv4 automatically (most have "Happy Eyeballs" logic)
2. If it doesn't, your ISP might offer an IPv4-IPv6 translation gateway
3. Worst case, switch to a network with IPv4 fallback

This is increasingly rare. By 2026, over 75% of the top 10,000 sites support IPv6.

Frequently Asked Questions

Should I switch my home network to IPv6?

If your ISP and router support it (most do since 2020), it's often enabled by default. You don't need to manually switch. Check your router admin panel to verify.

Does IPv6 make my internet faster?

Marginally yes. IPv6 connections skip the NAT translation step at the router, which can shave 1-5 milliseconds off latency. You won't notice in normal browsing.

Can I be tracked more easily on IPv6?

Without privacy mitigations, yes. With modern OS defaults (iOS, Android, Windows 10+), your device randomizes its IPv6 address every few hours, which makes tracking harder than it would be otherwise.

What's the difference between IPv6 link-local and global?

Link-local addresses (starting with fe80::) only work on your local network. Global addresses are reachable from anywhere. Most devices have both.

Why does my IP location seem more accurate on IPv6?

Some ISPs assign IPv6 addresses geographically. The address itself encodes information about which regional pool it came from, which can give better geolocation than IPv4 NAT-shared addresses.

Related Reading

• Why Does My IP Location Show the Wrong City
• Does Incognito Mode Hide Your Location
• Complete GPS Accuracy Guide

Bottom Line

IPv4 is running out and being supplemented by IPv6. Your devices likely use both. IPv6 is slightly faster, slightly less private by default, and inevitable. You don't need to do anything; the transition is happening automatically. Check your current IPs at WhatIsMyLocation.