The ultimate speed test test FAQ

Which speed test is best depends on what you want.

RealSpeed is a great speed test if your router supports RealSpeed. If so, it will measure your internet speed twice, once from your router and once from your device.

If RealSpeed doesn't work, we recommend Down at a Glance (based on M-Lab).

If you are having trouble with the download speed provided by your ISP, you should use the speed test recommended by your ISP to identify these issues.

An internet speed test is a tool (website, app, program) that measures the maximum amount of data you can receive per second. This "downloadspeed" is expressed in megabits per second (Mbps).

Note that in most cases the bandwidth provided by the ISP is not measurable because the home network is the weakest link.

A good speed test site is
1. Accurate and consistent
2. Free to use
3. Easy to use
4. Privacy friendly
5. Informative
6. Fast
7. Secure

With these requirements in mind, Down at a Glance is the best speed test out there.

Based on these criteria RealSpeed is second.

Assuming you want to know if your internet is working fine first check Internet Speed at a Glance.

If you want to know your internet speed in detail, it is best to use RealSpeed.

When your browser doesn't support RealSpeed, then use Down at a Glance. Before you start measuring, check whether the home network you are using can handle the bandwidth to be measured. In general it's best to test with a wired network to rule out Wi-Fi issues. Because large downloads have a huge impact on the speed measured, it is recommended to test on an updated system as a sole user.

Note that all modern speed tests need JavaScript.

Yes, Ookla's Speedtest does -like all other speed tests- consume data. In general the amount of data consumed depends on two factors:

1. The internet speed you measure
2. The speed test you use

Ookla's Speedtest consumes a lot of data, it is one of the least data efficient speed tests.

Two speed tests measure your true internet speed. These speed tests are:
1. True Speed at a Glance
2. SpeedOf.me

When you use SpeedOf.me, then use the max value to test your true internet speed.

Note that your true internet speed is circa 12% higher than the advertised internet speed.

Before you start measuring, check whether the home network you are using can handle the bandwidth to be measured. In general it's best to test with a wired network to rule out Wi-Fi issues. Because large downloads have a huge impact on the speed measured, it is recommended to test on an updated system as a sole user.

Note that above the 100 Mbps even SpeedOf.me doesn't measure your true internet speed (we were not able to test True Speed at a Glance above the 100 Mbps).

Which speed test is most accurate depends on the speed you measure (or expect to measure).

M-Lab is the only speed test that appears in the top 3 of most accurate speed tests for every speed tested.

In theory M-Lab based speed tests like Down at a Glance should also be fine.

However when RealSpeed works, you are able to test your internet speed direct from your router.

Internet Speed at a Glance is the fastest speed test there is. That makes Internet Speed at a Glance also the speed test with the smallest carbon footprint.

Cloudflare, Down at a Glance, Internet Speed at a Glance, LibreSpeed and True Speed at a Glance are the most privacy-friendly speed tests.

Down at a Glance, Internet Speed at a Glance and True Speed at a Glance are by far the most accessible speed tests there are.

These speed tests comes out on top with accessibility tests such as Achecker, Tingtun and WAVE. Manual testing confirms that these speed tests are by far the most accessible speed tests.

The best internet speed tests are:
(1) RealSpeed
(2) Down at a Glance
(3) Google Fiber
(4) M-Lab
(5) Internet Speed at a Glance
(6) Your ISP's speed test

Short answer: Yes

Long answer:
More often than not, your ISP offers a speed test based on the Ookla Speedtest (a sample shows at least 5 out of 6). Such a mainstream speed test measures the download speed just as good as the Ookla Speedtest.

There are numerous speed tests. This is mainly because many ISPs offer their own speed tests. However, these speed tests are not unique. Many ISP speed tests are Ookla clones. The number of truly unique speed tests is limited. We estimate there are less than 100.

Google Fiber is accurate. It is a mainstream speed test that accurately measures advertised speed. Google Fiber is a highly recommended speed test. It was the number 1 speed test in the ultimate speed test test of 2020 and has the highest overall score in the ultimate speed test test of 2022.

Ookla Speedtest is accurate. It is a mainstream speed test that accurately measures advertised speed. It is almost impossible to rate the Ookla Speedtest as inaccurate. After all, almost every ISP recommends using the Ookla Speedtest.

Ookla Speedtest is a reliable speed test, that is the speed test is accurate. However, we find the Ookla Speedtest far from privacy-friendly.

Ookla Speedtest is not a privacy-friendly speed test. In fact, it's the least privacy-friendly speed test out there.

There are many speed tests that are similar to Ookla Speedtest.

Some examples are:
- Cloudflare
- Down at a Glance
- Google Fiber
- M-Lab
- RealSpeed

Yes, there are better speed tests than Ookla. Down at a Glance, Google Fiber, M-Lab and RealSpeed are better than Ookla.

Large downloads (and TOR) have the biggest negative impact on your internet speed.

Your home network can have a very strong negative impact. If so, you probably have low and highly variable test results.

The test server used does not affect your internet speed.

Depending on the speed test used, the test server used can affect the measured internet speed.

However, in most speed tests, the test server used does not significantly affect the measurement of your internet speed.

As long as you use a modern browser (Chrome, Edge, Firefox), this will not affect your internet speed.

As long as you are running a modern updated operating system (Linux, OS X, Windows), it will not affect your internet speed.

Other active programs have no significant negative effect on your internet speed. However, intensive calculations can make it difficult to measure your internet speed properly.

The Domain Name System (DNS) server you are using will not affect your internet speed.

Video streaming uses some of your internet speed. Your internet speed as provided by your ISP does not change.

Depending on the speed test used, the use of video streaming can affect the measurement of your internet speed.

TOR uses a lot of your internet speed. Your internet speed as provided by your ISP does not change.

If you measure your internet speed while using TOR, the measured speed will be significantly slower.

Downloading files uses some of your internet speed. Your internet speed as provided by your ISP does not change.

If you measure your internet speed while downloading files, the measured speed will be significantly slower.

Depending on the VPN (Virtual Private Network) used, this can significantly affect your internet speed.

Research shows that there are major differences. There are VPNs that do not have a significant influence, but also VPNs that do have a significant influence.

Note that your internet speed as provided by your ISP does not change with the use of VPN.

The hardware you use (computer, Wi-Fi router, Powerline) can affect your internet speed.

This will be especially the case when the specifications of your hardware are less than the download speed provided by your ISP.

Note that the slowest part of your network determines your internet speed.

The influence of malware on your internet speed cannot be determined generically. You can assume that malware is using some of your internet speed.

Hence, malware is likely to negatively impact your internet speed. How much that is depends on the malware on your system.

Wi-Fi uses a specific part of the radio frequency (RF) spectrum. Concrete, brick and masonry significantly dampen the radio signals used by Wi-Fi. The radio waves from a microwave oven interfere with Wi-Fi radio signals.

The location of your WiFi router can therefore greatly affect your internet speed.

The time of day can affect your internet speed. It depends on your internet subscription and the quality of your Internet Service Provider's (ISP's) network.

Other devices and users will use some of the available internet speed. Your internet speed as provided by your ISP does not change.

If you measure your internet speed while other devices and users are using the internet, the measured speed may be slower.

This depends on the internet usage by the other devices and users.

The required internet speed depends on the number of users and the type of use. As a rule of thumb, moderate use of the internet requires a download speed of 8 Mbps per user.

The required download speed for video streaming in HD (High Definition) television quality is 5 Mbps per screen. This requirement is independent of the streaming platform. Note: Netflix has developed the Fast speed test so that you can easily test whether your internet speed is good enough for Netflix.

For populare gaming platforms like the Xbox, PlayStation, and Nintendo Switch you need a download speed of 3Mbps.

It depends on the platform you use. For example Zoom requires 3.8 Mbps up and 3.0 Mbps down for a video call. MS Teams requires 4 Mbps up and down.