How to Use Google Speed Test and How It Differs from Fast.com
If you search Google for "internet speed test", you can measure your connection speed right inside the search results. This article first explains how to use Google's speed test and how to read the results.
It then compares Fast.com, Speedtest.net, ISP-branded tests and this site, explains why the results often disagree, and suggests which tool fits which purpose. It does not declare any tool the best. It only states facts that could be confirmed on each provider's official pages.
How to use and read Google's speed test
Google's speed test is provided by Google in partnership with Measurement Lab (M-Lab). M-Lab is a collaborative project that publishes internet measurement data for research.
How to use it
- Search on Google. Google's help page describes searching for "internet speed test".
- Click "Run speed test" in the search results.
- The result appears in about 30 seconds.
The help page does not say what appears for searches in other wordings or languages. It also notes that the test is not available in some countries and regions.
How to read the results
The test shows three values: download speed (Mbps), upload speed (Mbps) and latency (ms). Latency is the time it takes for data to be sent and a response to come back. It affects games and video calls. This site uses the following common thresholds.
| Item | Too slow / poor | Standard / good | Plenty / very good |
|---|---|---|---|
| Download | Under 10 Mbps | 10–30 Mbps | 30 Mbps or more (100 Mbps or more is fast) |
| Upload | Under 5 Mbps | 5–10 Mbps | 10 Mbps or more |
| Ping (latency) | 50 ms or more | 20–50 ms | Under 20 ms |
More detailed guidelines are in What Is a Good Internet Speed? How to Read Speed Test Results and What Is a Good Ping? Jitter Explained and How to Lower Ping.
Things to keep in mind
- The upper limit is 700 Mbps. The help page states that on faster connections the result may show lower than the actual speed. Keep this in mind on plans such as 1 Gbps fiber.
- Data usage per test is about 4.4 MB outside the US (about 9.4 MB inside the US). On a mobile connection, data charges may apply.
- Your IP address is shared with M-Lab. M-Lab publishes test results, including IP addresses, for research.
M-Lab's standard test, NDT (current version ndt7), runs over WebSocket (a mechanism that lets the browser and server exchange data in both directions) and uses a single TCP connection. By specification, each direction is measured for at most 10 seconds. However, Google's help page does not say whether the test in the search results uses exactly this method.
Comparing the main speed test tools
The table below summarizes the differences between the main tools. Where a provider's help or official pages do not cover a point, it is marked "not stated" or "not published".
| Item | Google (M-Lab) | Fast.com | Speedtest.net | This site |
|---|---|---|---|---|
| Provider | Partnership between Google and M-Lab | Netflix | Ookla (a subsidiary of Ziff Davis) | Run by an individual |
| Method and number of connections | Not stated in the help page (M-Lab's NDT uses WebSocket and one connection) | Multiple transfers to and from Netflix servers. The settings screen has a field for the number of parallel connections | Mainly TCP (port 8080) with multiple connections, adding connections during the test as needed. HTTP is a fallback | Open-source LibreSpeed (LGPLv3) |
| Test servers | Not stated in the help page (M-Lab's privacy policy says data is usually collected by the nearest server) | Netflix servers. Locations and selection method are not published | A network of servers run by ISPs and others. Pings up to 5 nearby servers and picks the one with the shortest ping. Can be changed manually | Our own server in Sapporo plus public mirrors in 37 locations worldwide; the one with the lowest ping is chosen automatically (usually "Tokyo" from Honshu, Japan's main island) |
| Displayed values | Download, upload, latency | Download (upload and latency under "Show more info"). Unloaded and loaded latency | Download, upload, ping, jitter. Ping in three stages: idle, during upload, during download | Download, upload, ping, jitter |
| Apps | Not stated in the help page (run from search results) | Yes (iOS and Android, "FAST Speed Test") | Yes (iPhone, iPad, Mac, Apple TV, Android, Windows) | No (measures in the browser) |
| Ads and data handling | IP address shared with M-Lab. M-Lab publishes results including IP addresses | The FAQ states there are no ads. Collects IP addresses, measurements and more; states that it does not sell personal information | The official help states the site shows ads (including interest-based ads via ad networks) | No ads or third-party trackers |
| Login | Not stated as required | Not stated as required | Not required. Creating an account lets you keep all your results in one place | Not required |
Speedtest.net's help pages are not consistent about the number of servers: one page says "more than 5,500" and another says "about 3,000". How this site works is also described in Privacy Policy and About.
ISP- and carrier-branded speed tests
Many internet providers and mobile carriers offer their own speed test. These tests usually measure to a server inside the provider's own network. Because the data does not have to leave that network or cross the wider internet, the result tends to read higher than a test to an outside server. It shows how fast your line is up to the provider, but not necessarily how fast the sites and services you actually use will feel.
Such a test is useful as one reference point, for example when you report a problem to your provider. Keep in mind that a provider can change or withdraw its own test at any time, so it is better not to rely on it as your only tool for long-term records.
Why results differ between tools
Even on the same connection, the numbers can differ widely from tool to tool. There are four main reasons.
- Different server locations. The farther the server, the higher the ping and the harder it is to reach full speed. Speedtest.net's help also explains that distant servers tend to give slower results.
- Different numbers of connections. A method that uses only one connection and a method that combines several can give very different results, especially on fast lines.
- Different limits and calculations. Google's limit is 700 Mbps. Speedtest.net drops some of the fastest and slowest values before averaging.
- Different devices, browsers and Wi-Fi. On fast lines, a device's wireless performance and the browser are said to make a difference.
When comparing, the basic rule is to use the same device, the same connection and the same time of day. The steps are explained in detail in How to Run an Accurate Speed Test: Steps and How Many Times.
Which tool to use for what
| Purpose | Suitable approach |
|---|---|
| Just a quick check | Run it from Google's search results, or simply open Fast.com. Both let you measure as soon as the page opens |
| Checking whether video will play smoothly | Fast.com is provided by Netflix and measures speed to Netflix servers. By this site's thresholds, 30 Mbps or more download is the guideline for 4K video |
| Checking ping for gaming | Use a tool that lets you choose a nearby server, and check ping and jitter. By this site's thresholds, ping under 20 ms is "very good" and jitter under 10 ms is "stable" |
| Tracking over time | Choose a tool whose test server does not change each time, and record results under the same conditions at different times of day. Speedtest.net lets you keep a history with an account |
Do not judge from a single result from a single tool. Measuring a few times with two or more tools shows the trend more clearly. You are welcome to use this site's Free Speed Test as one of the tools you compare.
FAQ
- How do I use Google's speed test?
Search Google for something like "internet speed test" and click "Run speed test" in the results. Download, upload and latency appear in about 30 seconds.
- Is Google's speed test accurate?
Its help page says the test has an upper limit of 700 Mbps, so faster connections may show lower results. Results also change with server location and time of day. Comparing several tools makes it easier to judge.
- Can Fast.com measure upload speed?
Yes. At first only download is shown. Click "Show more info" to see upload and latency.
- Why does my ISP's own speed test show higher numbers?
An ISP's own test usually measures to a server inside its network, so the data does not travel across the wider internet. That tends to give higher numbers than a test to an outside server. Use it as one reference alongside other tools.
- Why do results differ between tools?
Because the server location, number of connections and calculation method differ between tools. Compare on the same device at the same time of day.
Test your connection now
Download, upload, ping and jitter, right in your browser. No sign-up, no ads.
Start the speed testRelated guides
- How toHow to Run an Accurate Speed Test: Steps and How Many Times
A checklist for running an accurate internet speed test: why results vary, what to watch for on a phone, and how many times to test.
- GuidelinesWhat Is a Good Internet Speed? How to Read Speed Test Results
What download, upload, ping and jitter mean on a speed test, with tables of good internet speeds by activity and connection type, and what to do next.
- GuidelinesWhat Is a Good Ping? Jitter Explained and How to Lower Ping
What ping and jitter mean, how many ms counts as good, the minimum ping set by distance, why test servers differ, and how to lower ping, with tables.
Sources
- Google Search Help: About the internet speed test (retrieved 2026-11-12)
- M-Lab: NDT (Network Diagnostic Tool) (retrieved 2026-11-12)
- M-Lab ndt7 protocol specification (GitHub) (retrieved 2026-11-12)
- M-Lab Privacy Policy (retrieved 2026-11-12)
- FAST.com (Japanese page and FAQ) (retrieved 2026-11-12)
- Netflix: FAST.com Privacy Statement (retrieved 2026-11-12)
- App Store: FAST Speed Test (Netflix, Inc.) (retrieved 2026-11-12)
- Google Play: FAST Speed Test (retrieved 2026-11-12)
- Speedtest Help: Assessing accuracy (test method) (retrieved 2026-11-12)
- Speedtest Help: Why does Speedtest need to find a nearby server? (retrieved 2026-11-12)
- Speedtest Help: Adjusting servers (retrieved 2026-11-12)
- Speedtest Help: Assessing test results (retrieved 2026-11-12)
- Speedtest Help: Downloading apps (retrieved 2026-11-12)
- Speedtest Help: Why are there advertisements on Speedtest? (retrieved 2026-11-12)
- Speedtest Help: How do I create a Speedtest account? (retrieved 2026-11-12)