How to Test Your Internet Speed

Here’s a step-by-step guide on how to test your internet speed, common causes of slow internet, and what to do if your connection isn’t meeting expectations.

What is an internet speed test?

An internet speed test is a tool that measures the current performance of your connection. In just a few seconds, it gives you insight into various metrics, including things like:

Download speed – The rate at which your connection receives data from the internet. This impacts activities like streaming video, browsing, and downloading files.
Upload speed – The rate at which your connection sends data to the internet. This affects tasks such as video conferencing, sending large files, and online gaming.
Ping (latency) – The time it takes for data to travel between your device and a server. Lower latency is better for real-time activities like video calls or gaming.
Jitter – A measure of how consistent the latency is. Lower jitter means a more stable connection.

These numbers can help you figure out whether your current plan is performing as expected—and whether your home setup is optimized for your needs.

Key terms to know before testing

Understanding a few basic terms can help you interpret your speed test results more accurately:

Mbps (Megabits per second): The standard unit for measuring internet speed. Both download and upload speeds are typically measured in Mbps.
Bandwidth: The maximum amount of data your connection can transmit in a given amount of time. Higher bandwidth supports more users and devices.
Packet loss: Occurs when data traveling across the network fails to reach its destination. Even small amounts of packet loss can cause disruptions in streaming or calls.
Buffer bloat: A buildup of data in the network queue, causing noticeable slowdowns.
Throughput: The actual speed at which data is transmitted. This may vary from the bandwidth depending on network conditions.
Ping spikes: Sudden increases in latency that can lead to noticeable delays or interruptions.

Running a speed test is quick and easy – but how does an internet speed test work exactly? When you start a test, your device (the client) connects to a nearby server. The test measures how fast you can download data from that server, how quickly you can upload data back, and how long it takes a small signal (ping) to make a round trip – that’s your latency – which shows how responsive your connection is.

Now that you have some background, here’s how to make sure your test gives you accurate, useful results:

Step 1: Use a trusted speed test tool

Choose one of the many recommended internet speed test sites available online, most of which are quick, easy, and free to use.

Step 2: Prepare your network for testing

A few quick tweaks before testing can make your results far more accurate:

Close background apps and tabs that use the internet, such as streaming services, cloud backups, or software updates.
Disconnect extra devices (smart TVs, consoles, tablets) to prevent them from sharing your bandwidth.
Connect directly to your router with an Ethernet cable if possible. This gives a clearer picture of your maximum speed.
If testing over Wi-Fi, move close to your router/gateway and minimize walls or interference.
Run tests at different times of day to see if speeds dip during busy evening hours.

Step 3: Start the test

Open your chosen speed test site and click Go (or the site’s equivalent button). The tool will automatically measure your download, upload, and ping times – you don’t need to adjust anything.

Step 4: Review and save your results

Take a screenshot or jot down your numbers. Try running the test a few times over a day or two; consistent patterns (like slower evening speeds) can help you spot congestion or other trends.

How to interpret your speed test results

Compare your results to what your internet plan promises. If your speeds are regularly much lower than expected, or your ping times are high, it might be worth rebooting your router, checking for firmware updates, or contacting your provider. You can also test using different servers or devices to confirm whether the issue lies with your equipment or the network itself. This chart gives you a quick glance before we get into the details.

What You Notice	What It Might Mean	Quick Next Steps
Speeds are much lower than your plan promises	Network congestion, weak signal, or outdated router/gateway	• Restart your router or gateway. • Run tests at different times to see if speeds improve. • Move gateway/router to a central, open location. • Contact your provider if speeds remain low.
Ping (latency) is high or inconsistent	Congestion, weak Wi-Fi signal, network interference, or distance to server	• For Wireless: Move closer to your router/gateway, switch to 5GHz, and reduce interference from electronics. • For wired: Check cables and connections. • Limit other devices using bandwidth. • Restart your router/gateway and retest.
Wi-Fi signal is weak or drops often	Physical obstacles, distance, or interference	• Place router/gateway in a central, elevated, open spot. • Keep away from walls, appliances, and electronics. • Consider a Wi-Fi extender or mesh system for better coverage.
Speeds vary between devices	Older devices or limited Wi-Fi capabilities	• Check device Wi-Fi standard (5GHz or Wi-Fi 6). • Update software/firmware. • Use newer devices if needed for high-speed tasks.
Speeds slow at certain times of day	Network congestion in your area	• Run tests at different times to spot patterns. • Schedule heavy downloads or streaming during off-peak hours. • Share results with your provider if the issue persists.
Older router, modem, or gateway	Outdated hardware may limit speed and reliability	• Check for firmware updates. • Upgrade equipment to support modern Wi-Fi standards and faster speeds.
Speed seems fine, but device still lags	Background apps, updates, or malware using bandwidth	• Close unnecessary apps and pause updates. • Scan for malware. • Check which apps use data and limit nonessential ones.

Common causes of slow internet speeds

If your connection isn’t meeting expectations, here are a few possible reasons:

1. Network congestion

At certain times of the day, especially during the evening or weekends when everyone is at home, internet speeds can slow down because too many people are using the same network at once. This is particularly common in places like apartment buildings or neighborhoods where multiple households are connected to the same infrastructure. Think of it like a traffic jam on the highway: when more cars (or users) get on the road (or network), everything slows down. If you’re experiencing sluggish internet during peak hours, this could be the culprit.

Tip: If you can, try to schedule your high-bandwidth activities (like large downloads or streaming) during off-peak hours, like late at night or early in the morning.

2. Weak Wi-Fi signal

Your Wi-Fi router broadcasts a signal to your devices, but that signal can weaken depending on how far you are from the router and any obstacles between you and it. Thick walls, floors, and even large metal objects like fridges can block the signal, leading to slow speeds or dropouts. Also, devices like microwaves or cordless phones can interfere with your Wi-Fi, especially if you’re on the 2.4 GHz band (which is a common frequency used by many devices).

Tip: Try moving your router to a more central, open location in your home and away from electronic devices that might cause interference. The closer your devices are to the router, the stronger the connection will be. Another option is to consider upgrading to a Mesh Wi-Fi system, which can enhance coverage and deliver a stronger signal throughout more areas of your home.

3. Outdated router/modem/gateway

If your router, modem, or gateway is more than a few years old, it may not support newer, faster internet speeds or the latest Wi-Fi technology (like Wi-Fi 6, Wi-Fi 7, or faster 5GHz frequencies). As a result, you might be paying for high-speed internet, but your hardware is holding you back from getting the full benefit.

Tip: Upgrading to a newer model that supports the latest standards can give you a noticeable improvement in speed and reliability.

4. ISP speed management

Some internet service providers (ISP) limit you to a certain amount of data in a month, depending on you plan.

Tip: If you notice your internet speeds slowing down during specific times of the month, check if your ISP has a data cap or if they manage speeds after a certain usage limit. If this is a problem, consider reaching out to your provider or exploring other plan options.

5. Device limitations

Just like old routers, modems, and gateways, not all devices are built to handle high-speed internet. Older phones, laptops, or tablets might not support the newer, faster Wi-Fi frequencies like 5GHz or Wi-Fi 6 or Wi-Fi 7. This means even though your router is capable of faster speeds, your device might be stuck on slower speeds because it can’t take advantage of the latest technology.

Tip: Check if your device supports newer Wi-Fi standards like 5GHz or Wi-Fi 6 or 7. If not, you might consider upgrading to a newer device that supports these faster connections, especially if you need to do activities like HD streaming or online gaming.

6. Electromagnetic interference

Electromagnetic interference (EMI) happens when signals from other devices (like microwaves, cordless phones, baby monitors, or even neighboring Wi-Fi networks) mess with your Wi-Fi signal. EMI can cause your Wi-Fi signal to drop or slow down, leading to buffering or lag.

Tip: Try moving your router away from devices like microwaves or cordless phones. Also, if you’re using the 2.4GHz band (which is more susceptible to interference), consider switching to 5GHz for less interference and better performance.

7. Malware or background activity

Malware (or viruses) can use up internet bandwidth, slowing down your connection without you realizing it. Additionally, background apps – like software updates, cloud backups, or streaming apps – might be using bandwidth while you’re doing something else.

Tip: Do security checks. Regularly scan your devices for malware and close any unnecessary apps that might be running in the background. Check your device’s task manager (for PCs) or app settings (for smartphones) to see what’s using your bandwidth, and shut down anything that doesn’t need to be running.

What to do if your internet speed is slower than expected

If your internet speed test shows consistently low numbers, try these steps:

Restart your router and modem (or gateway): Power-cycling your equipment can often resolve temporary issues.
Update your router’s firmware: Check for updates through your router’s settings or companion app.
Secure your network: Make sure your Wi-Fi is password-protected to prevent unauthorized use.
Limit background activity: Pause large uploads, downloads, or software updates while testing or troubleshooting.
Contact your provider: Ask your ISP to check for issues, or recommend plan upgrades if needed. You may also consider switching ISPs if they don’t meet your needs.

Testing your internet speed helps ensure your connection is fast, reliable, and fits your lifestyle. Whether you’re streaming, gaming, hosting virtual meetings, or working from home, knowing how your network is performing puts you in a better position to improve it when needed.

Internet speed tests: 15 FAQs

1. What is a good internet speed test result?

A “good” result depends on your needs: fast enough for streaming, gaming, video calls, or downloads without lag or buffering.

2. What are the units of measurement for an internet speed test?

Internet speed is usually measured in Mbps (megabits per second) for download and upload speeds. Ping/latency is measured in milliseconds (ms).

3. How does an internet speed test work?

It measures how quickly your device can download and upload data to a server and how long it takes for a signal to travel back (ping).

4. What are the limitations of an internet speed test?

Results can vary due to Wi-Fi interference, network congestion, device limits, server location, or background apps.

5. What factors affect internet speed test results?

Device type, connection type, router/gateway location, network congestion, and background activity.

6. Can I run a speed test on my phone or tablet?

Yes. Most browsers and apps allow speed testing on mobile devices.

7. Does the type of connection (wired vs. wireless) affect speed test results?

Speeds can differ between wired and wireless connections due to how data is transmitted, the distance to your router or gateway, and other environmental factors.

8. How often should I test my internet speed?

Test occasionally or if you notice slow performance, or at different times of day to check for patterns.

9. What causes speed test results to vary throughout the day?

Network congestion, peak usage hours, and shared local infrastructure can slow speeds at certain times.

10. What should I do if my speed test results are consistently low?

Restart your router or gateway, check for interference, update firmware, test multiple devices, and contact your ISP if needed.

11. Can internet speed tests detect issues with my ISP?

They can indicate slow speeds or high latency, but they can’t pinpoint every ISP issue without additional troubleshooting.

12. Does my router or modem impact speed test accuracy?

Yes. Older or low-quality hardware can limit speeds and affect test results.

13. What’s the difference between Mbps and MBps?

Mbps = megabits per second (internet speed); MBps = megabytes per second (file size/speed). 1 MBps = 8 Mbps.

14. How do I test internet speed on smart TVs or gaming consoles?

Most devices have a built-in network test under Settings, or you can connect them to a computer or phone running a speed test.

15. Are free internet speed tests reliable?

Yes, most are accurate for basic testing, but results can vary by server location, time of day, and device used.

Choosing the right internet plan

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How to Test Your Internet Speed: 4 Steps

What is an internet speed test?

Key terms to know before testing