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How to Disable IPv6 on Mac (and When Not To)

macOS removed the IPv6 Off option from System Settings, but networksetup can still do it. Here's how, and why you usually shouldn't.

networksetup -setv6off Wi-Fi

Turn IPv6 off for the Wi-Fi service.

intermediate3 minNeeds: Administrator account

When to use it

Disabling IPv6 is a troubleshooting step for broken IPv6 on a specific network: sites that load slowly or not at all while IPv4 works, often because a router or VPN mishandles IPv6. On a healthy network it gains nothing, and some Apple features prefer IPv6.

Steps

  1. Check whether IPv6 is the problem

    If curl -6 https://example.com fails but curl -4 https://example.com works, IPv6 on this network is broken.
    curl -6 -sS -o /dev/null -w '%{http_code}\n' https://example.com

  2. Turn IPv6 off

    Use the exact service name from System Settings.
    networksetup -setv6off Wi-Fi

  3. Verify

    Only the link-local fe80:: address or no inet6 line should remain.
    ifconfig en0 | grep inet6

  4. Turn it back on later

    Restore automatic IPv6 once the network is fixed.
    networksetup -setv6automatic Wi-Fi

Output explained

networksetup prints nothing on success. Check the result in System Settings › Network › Details › TCP/IP: Configure IPv6 shows Off while it's disabled, and Automatically when restored.

networksetup -setv6LinkLocal Wi-Fi is a middle ground: IPv6 only on the local link, no global addresses.

Options and variations

FlagMeaningExample
-setv6off SERVICEDisable IPv6networksetup -setv6off Wi-Fi
-setv6automatic SERVICEAutomatic IPv6 (default)networksetup -setv6automatic Wi-Fi
-setv6LinkLocal SERVICELink-local onlynetworksetup -setv6LinkLocal Wi-Fi
-getinfo SERVICEShow the current IPv6 settingnetworksetup -getinfo Wi-Fi

Common errors

ErrorCauseFix
** Error: The parameters were not valid.Wrong service nameList names with networksetup -listallnetworkservices.
Problem persists after disabling IPv6IPv6 wasn't the causeTurn it back on and troubleshoot DNS or the router.

Do it in the app

LightAtom's connections view shows which connections use IPv6 and which IPv4, so you can see what IPv6 is actually doing before turning it off.

Frequently asked questions

How do I disable IPv6 on a Mac?

Run networksetup -setv6off Wi-Fi in Terminal (use your service's name). System Settings only offers Automatically, Manually or Link-local only.

Should I disable IPv6 on my Mac?

Usually not. Do it only to work around a network that breaks IPv6, and turn it back on afterwards. Disabling it doesn't improve speed or privacy on a working network.

Does disabling IPv6 fix slow internet?

Only if IPv6 on your network is broken, which shows as long delays before pages load. Test with curl -6 and curl -4 to check first.

Related

LightAtom team

The people who build LightAtom, a network monitor for macOS.