Speed test results differ between browsers on a VPN

You run a speed test in two browsers on the same laptop, with the same VPN connected, and get different numbers. That does not automatically mean one browser is broken or the VPN is failing.

Compare the browsers under the same conditions first. The Speed Test measures download speed, upload speed, ping, and jitter. A few repeat runs can show whether the difference is consistent or just normal variation.

Compare the browsers fairly

1. Open the Speed Test in your first browser. Keep the VPN connected, and use the same Wi-Fi or wired connection you normally use.
2. Run the test and note the download, upload, ping, and jitter results. Also note the VPN location and, if you can see it in the VPN app, the connection protocol.
3. Open the same test in the second browser. Keep the VPN connection and location unchanged, and avoid changing Wi-Fi, power mode, or other network settings between tests.
4. Run three tests in each browser, one after another. Alternate browsers between runs, for example, first browser, second browser, first browser, second browser. Do not run two speed tests at the same time.
5. If it is safe and allowed, repeat the comparison with the VPN disconnected. Do this only if you are comfortable sending test traffic without the VPN and your work or school rules allow it.

A single result is a snapshot. Repeating the tests in a short period makes it easier to tell a browser-specific pattern from a temporary change in network load. For more about ordinary speed test variation, see why two internet speed tests give different results.

What the results mean

The browsers get similar results

The browser choice probably is not the main cause of your speed. If both results are lower with the VPN on than off, the VPN route or server may be limiting throughput. A VPN sends your traffic through another server, which can add distance and processing time.

One browser is slower in every run

A consistent gap points to a difference in how that browser is set up, or to different routing. A VPN extension may send traffic through a tunnel in one browser while the other uses your computer's VPN app. Extensions, background tabs, or a browser with a proxy setting can also affect the comparison.

If you use a browser VPN extension, the VPN Leak Test can check whether your real IP appears through IPv6 or WebRTC while the VPN is on. It does not measure speed or prove that every kind of traffic uses the VPN.

Results jump around in both browsers

Changing results usually mean the connection or test conditions are varying. Other people using the network, cloud backups, video streams, and a VPN server under load can all affect throughput. Ping and jitter can move even when download speed looks similar.

Download speed changes, but ping and jitter stay close

The difference may be about how much data the browser test can transfer during the run, rather than a large change in responsiveness. Compare several runs and focus on the repeated pattern, not the highest single number.

Ping or jitter changes a lot between browsers

The browsers may be using different routes, or the results may have been taken during changing network conditions. Check whether one browser has a VPN extension, proxy, or split-tunnel rule that the other does not.

How to fix an unexpected difference

1. Stop other network activity. Pause large downloads, cloud backups, video streams, and software updates on the laptop. If other devices are using the same connection heavily, wait until they are idle before comparing again.
2. Use the same VPN connection in both browsers. If you use a VPN app on the laptop, make sure it stays connected to the same location throughout the test. If you use a browser extension, check whether the extension is enabled in both browsers and whether it selects the same location.
3. Check split tunneling and browser exclusions. Some VPNs let you exclude an app from the tunnel, or route only selected apps through it. Review the VPN app's settings and make sure the browsers are treated the same way. For the built-in VPN settings, Windows 11 has Settings › Network & internet › VPN, and macOS has System Settings › VPN. Third-party VPN apps may manage these options in their own settings.
4. Close extensions that change traffic. Temporarily turn off proxy, VPN, privacy, or traffic-filtering extensions in both browsers, then repeat the comparison. Change one thing at a time so you can see which setting matters.
5. Restart the slower browser and reconnect the VPN. Close the browser completely, reconnect the VPN, and run the tests again. This can clear a stuck browser connection or refresh a VPN session.
6. Compare the VPN off only when appropriate. A brief test without the VPN can help show whether the VPN route is involved. Avoid this on sensitive networks or when a workplace, school, or service requires the VPN to stay connected.

Why browser speed tests can differ

A browser speed test measures what happens between that browser and the test server during a short period. It is not a direct reading of your internet plan's maximum speed. The test exchanges data with our server to measure throughput, and the result can change with server load, network congestion, VPN routing, and browser activity.

A system-level VPN usually handles network traffic from both browsers, but browser-specific VPN extensions can work differently. Split tunneling can also send one browser outside the VPN. If you use a work or school VPN, follow its rules rather than changing its route just to get a higher result.

For a useful comparison, keep the test, connection, VPN location, and general network conditions consistent, then compare the repeated results rather than chasing a single peak number.