How to Flush Your DNS Cache

Flushing your DNS cache clears the locally stored DNS records on your device, forcing it to fetch fresh results from DNS servers. This is one of the first troubleshooting steps when a website isn't loading correctly or when you've recently made DNS changes.

Why Flush Your DNS Cache

Your operating system caches DNS lookups to speed up repeat visits. But this cache can become stale or incorrect:

• After changing DNS records — you updated an A record or switched nameservers, but your browser still shows the old IP
• After a DNS migration — you moved to a new DNS provider like DNScale and want to verify the change immediately
• Website not loading — the cached record points to a server that's no longer responding
• DNS poisoning concerns — a corrupted cache entry is returning the wrong IP address
• Troubleshooting connectivity — ruling out stale DNS as the cause of network issues

Flush DNS on Windows

Windows 10 / 11

Open Command Prompt or PowerShell as Administrator:

ipconfig /flushdns

You'll see: Successfully flushed the DNS Resolver Cache.

To verify the cache is empty:

ipconfig /displaydns

Reset the DNS Client Service

If flushing alone doesn't work:

net stop dnscache
net start dnscache

Flush DNS on macOS

The command varies by macOS version, but this works on macOS Monterey and later (including Ventura, Sonoma, and Sequoia):

sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder

Enter your admin password when prompted. There's no confirmation message — the command completes silently.

Older macOS Versions

Flush DNS on Linux

Linux distributions vary in their DNS caching behavior. Many don't cache DNS by default, but if you use systemd-resolved, dnsmasq, or nscd, here's how to clear them:

systemd-resolved (Ubuntu 18.04+, Fedora, Arch)

sudo systemd-resolve --flush-caches

Or on newer versions:

sudo resolvectl flush-caches

Verify with:

resolvectl statistics

dnsmasq

sudo systemctl restart dnsmasq

nscd (Name Service Cache Daemon)

sudo systemctl restart nscd

Or invalidate just the hosts cache:

sudo nscd -i hosts

Flush DNS in Chrome

Chrome maintains its own internal DNS cache, separate from the OS cache. To clear it:

1. Open Chrome and navigate to: chrome://net-internals/#dns
2. Click Clear host cache
3. Optionally, also go to chrome://net-internals/#sockets and click Flush socket pools

Other Browsers

• Firefox: No built-in DNS cache flush. Restart the browser, or set network.dnsCacheExpiration to 0 in about:config
• Safari: Enable Develop menu (Preferences → Advanced), then Develop → Empty Caches
• Edge: Same as Chrome — navigate to edge://net-internals/#dns

When to Flush vs. When to Wait

Verify DNS Changes Without Flushing

Instead of flushing your cache, you can query a DNS server directly to check if your changes have propagated:

# Query Google's public DNS
dig example.com @8.8.8.8
 
# Query Cloudflare's DNS
dig example.com @1.1.1.1
 
# Query your DNScale nameserver directly
dig example.com @ns1.dnscale.eu

This bypasses your local cache entirely and shows what DNS servers are currently returning.

Understanding DNS Cache TTL

DNS caching is controlled by the TTL (Time to Live) value set on each record. When you flush your cache, you're clearing entries before their TTL expires.

Pro tip: If you plan to make DNS changes, lower the TTL to 300 seconds (5 minutes) a day before the change. After the change propagates, restore the original TTL. This minimizes the window where stale records are served. See DNS TTL Best Practices for more strategies.

Related Topics

• What Is TTL — how cache duration works in DNS
• DNS TTL Best Practices — recommended TTL strategies
• DNS Propagation Explained — why DNS changes take time

Conclusion

Flushing your DNS cache is a quick, safe operation that forces your device to fetch fresh DNS data. Whether you're troubleshooting connectivity issues or verifying DNS changes after updating records in DNScale, it's an essential tool in every administrator's toolkit.