How to check whether your router supports fair queueing

Downloads or uploads can make calls and games lag, even when your internet speed looks good. Fair queueing is a way for a router to manage traffic so one busy transfer is less likely to delay everything else.

You can look for fair queueing in your router’s settings, then check whether it makes a measurable difference. The Bufferbloat Test measures how much response time increases while downloading or uploading, but it cannot identify the router’s queueing algorithm by itself.

Test your router’s queueing behavior

1. Open the Bufferbloat Test. For the clearest router result, connect your computer to the router with Ethernet if possible.
2. Pause downloads, video streams, cloud backups, and other heavy network activity. Keep the test device in the same place and use the same connection for each run.
3. Run the test once with the router’s current settings. Note the grade and how much response time rises during download and upload activity.
4. Open your router’s app or administration page and look for settings named Smart Queue Management, SQM, Fair Queueing, FQ-CoDel, or CAKE. Labels vary by router.
5. If you find a queue management option, note its current state before changing it. Enable it only if you understand the setting, save the change, and repeat the test under the same conditions.

Keep a short record of the starting grade and the results after any change. One run can be affected by other traffic or temporary internet congestion, so repeat each test a few times before drawing a conclusion.

What the result means

The grade is good and response time rises only a little

Your connection is keeping delay low during the test load. That is consistent with effective traffic management, but it does not prove that the router uses fair queueing. A quiet network, a fast connection, or queue management elsewhere can also produce a good result.

The grade is poor or delay jumps under load

A long queue may be forming somewhere between your device and the test server. The router is one possibility, especially if the result improves after enabling SQM. Wi-Fi interference, other household traffic, or congestion at your internet provider can also affect the measurement.

Upload delay is much worse than download delay

The upload side may be the bottleneck. This is common when a connection has limited upload capacity and a device is sending large files or backing up data. A router setting that manages download traffic may not control upload traffic in the way you expect.

You find a fair queueing setting but the result does not improve

The feature may be disabled, configured for the wrong connection speed, or unable to manage the bottleneck you tested. It may also be active but make little visible difference on a connection that was not congested during the test.

How to check and improve the setup

1. Use a wired connection for the comparison. Wi-Fi adds its own delays and interference, which can hide changes in the router’s traffic handling. On Windows 11, check Settings › Network & internet to see whether you are using Ethernet or Wi-Fi. On macOS, open System Settings › Network and select the active connection.
2. Check that the network is otherwise quiet. Pause streaming, backups, game downloads, and large file transfers on other devices. If another device is using the connection heavily, the result may reflect that traffic as well as the router’s queue.
3. Look for queue management, not just a QoS label. QoS, or Quality of Service, can mean several things. Some routers only prioritize selected devices or applications. That is not necessarily fair queueing. Look for SQM, FQ-CoDel, CAKE, or an explicit fair queueing option in the router’s documentation or settings.
4. Set bandwidth limits carefully if SQM asks for them. Use repeatable measured speeds, not just the advertised plan speed. A starting limit around 90 to 95 percent of the speed you actually get may help the router control the queue, but the best value depends on your connection. Change one value at a time and retest.
5. Update the router software. Check the router’s administration page or manufacturer’s app for a firmware update. Menu names and update steps differ by model, so use the instructions for your router and avoid interrupting power during an update.
6. Retest after each change. Run several tests with the same wired or Wi-Fi connection and similar network activity. If the grade improves and loaded response time falls consistently, the setting is helping in your setup.

What the test can and cannot confirm

The Bufferbloat Test measures the effect of network load on response time and gives a grade from A+ to F. It does not read your router’s settings or tell you whether it uses CAKE, FQ-CoDel, or another algorithm. A better result after enabling a queue management feature is useful evidence that the change helped, but it is not a direct identification of the method.

If your router has no fair queueing or SQM option, check its product information or support documentation for the exact model and firmware version. If loaded delay remains high and the router cannot manage the queue, a router with supported SQM may be a practical upgrade. A poor test result alone is not enough to show that the router is defective.