How to change DNS settings to fix slow internet browsing

When websites take a long time to start loading, the problem may be linked to the Domain Name System (DNS). DNS translates a web address such as example.com into the numerical IP address used by your computer. If the DNS server is slow, overloaded, or temporarily unavailable, your browser can pause before a page begins to load.

Changing DNS settings will not increase the speed of your NBN plan or repair weak Wi-Fi coverage. It can, however, improve the time needed to find websites and may resolve browsing problems caused by unreliable name resolution. This is particularly useful when some sites load quickly while others stall or display DNS-related errors.

The steps below apply to Windows 10 and Windows 11 computers. They cover testing your current connection, selecting a dependable DNS service, changing settings safely, and reversing the change if browsing becomes less reliable.

Check whether DNS is causing the delay

Before changing anything, compare several websites in different browser tabs. If all online activity is slow, including video streaming, downloads and speed tests, the issue may involve Wi-Fi interference, the NBN connection, router performance, or an internet service outage. DNS is more likely to be involved when the browser waits before opening a site, while already-open pages and downloads continue normally.

Open Command Prompt by searching for Command Prompt in the Windows Start menu. Type nslookup www.microsoft.com and press Enter. Windows will show the DNS server being used and the time taken to return an address. You can try a few different domains to identify repeated delays or error messages such as “DNS request timed out” or “server failed”.

It is also worth restarting the modem or router before changing configuration. Turn it off, wait around 30 seconds, then switch it back on. Check whether the slowdown affects every device in the home. If phones, smart televisions and another computer are also having trouble, the router or ISP is a more likely source than Windows alone. For Australian households using an NBN connection in Sydney, Melbourne or Brisbane, check your provider’s outage page before making technical changes.

Choose a reliable DNS service

Your internet provider normally assigns DNS servers automatically. Providers such as Telstra, Optus and Aussie Broadband may use their own servers or route requests through partner networks. These can work well, but performance may vary by location, network congestion and maintenance. A public DNS service can offer a useful comparison.

Common options include Cloudflare at 1.1.1.1 and 1.0.0.1, Google Public DNS at 8.8.8.8 and 8.8.4.4, and Quad9 at 9.9.9.9 and 149.112.112.112. Quad9 focuses on blocking many known malicious domains, while Cloudflare is widely recognised for quick responses and a privacy-focused policy. Availability and performance can differ between suburbs, regional towns and rural areas, so no single provider is best for every Australian connection.

Avoid entering random DNS addresses found on unfamiliar websites. An untrustworthy DNS operator could redirect requests, record browsing activity, or send users to unsafe pages. Use the provider’s official documentation and record your original automatic settings before making any changes. If your workplace, school or managed business network supplies a specific DNS server, consult the administrator first.

Change DNS settings in Windows

In Windows 11, open Settings, select Network & internet, then choose Wi-Fi or Ethernet, depending on how the computer connects. Select the active network, locate DNS server assignment, and choose Edit. Change the setting from Automatic (DHCP) to Manual, enable IPv4, and enter the preferred and alternate DNS addresses. Select Save when finished.

Windows 10 uses a slightly different path. Open Settings, choose Network & Internet, then select Change adapter options. Right-click the active Wi-Fi or Ethernet connection, choose Properties, and open Internet Protocol Version 4 (TCP/IPv4). Select Use the following DNS server addresses, enter the preferred and alternate addresses, and apply the change.

For example, Cloudflare’s IPv4 addresses are 1.1.1.1 and 1.0.0.1. Google’s are 8.8.8.8 and 8.8.4.4. Do not alter the IP address, subnet mask or default gateway unless you have a specific reason. Changing unrelated network values can disconnect the computer from the router.

IPv6 may also be active on your network. Many Australian NBN services continue to operate mainly through IPv4, but some providers support IPv6. Leave IPv6 on unless you are troubleshooting a specific compatibility issue. If you decide to set custom IPv6 DNS addresses, use the values published by your chosen DNS provider rather than copying IPv4 addresses into the IPv6 fields.

Clear cached results and test the change

Windows stores recently resolved domain names in a local DNS cache. After changing servers, open Command Prompt as an administrator and run ipconfig /flushdns. A successful message confirms that the old cached entries have been cleared. Close and reopen your browser, then test websites that were previously slow.

You can also renew the network connection by running ipconfig /release followed by ipconfig /renew. This may briefly disconnect the computer. Another useful command is nslookup, which can confirm that the computer is now using the selected DNS server. The server name or address shown in the result should match the provider you entered.

Run a browser speed test and compare the result with your earlier experience rather than relying on one page load. If a site is still slow, try a different browser and connect the computer directly to the router with an Ethernet cable. This separates DNS performance from Wi-Fi signal problems, crowded 2.4 GHz networks and interference from neighbouring apartments, which can be common in dense areas of Melbourne or Sydney.

Private browsing, browser extensions and security software can also affect loading times. If only one browser is affected, temporarily disable non-essential extensions and check for pending updates. Do not disable antivirus protection for routine testing unless you have a safe, controlled reason and know how to restore it immediately.

Change the router or restore automatic DNS

Changing DNS on the router applies the setting to most devices in the home, including phones, tablets, gaming consoles and smart televisions. Open the router’s administration page, often shown on its label or in its manual, then look for Internet, WAN, Network or DNS settings. Enter the primary and secondary addresses, save the configuration, and restart the router if requested.

Router menus differ considerably. An NBN provider may supply a locked or customised modem that does not allow manual DNS changes. Some ISP services also require their own settings for authentication or support. If the router rejects the values, leave its configuration unchanged and set DNS on the individual Windows computer instead.

If browsing becomes worse, return Windows DNS to Automatic (DHCP). In the adapter’s IPv4 properties, select Obtain DNS server address automatically, save the setting, flush the DNS cache and restart the browser. This restores the DNS servers supplied by the router or ISP.

Persistent slow browsing usually needs broader troubleshooting. Check for malware, unwanted browser extensions, damaged Windows network components, outdated router firmware, failing hardware or a congested wireless channel. A computer repair service can test the connection, inspect the system for infections, optimise Windows and determine whether the fault lies with the PC, home network or NBN provider.