How to Run a Speed Test: Check Your Internet Speed

Few things frustrate more than paying for fast broadband and watching a loading spinner spin. An internet speed test is the simplest way to check whether your connection delivers what your provider promised — but getting an accurate result takes more than just clicking a button. This guide shows you how to run a speed test properly, which tools are most reliable, and what to do when your numbers fall short of the plan you’re paying for.

Average global fixed broadband speed (2023): 68 Mbps download / 26 Mbps upload (Ookla) ·
Speed tests run daily on Ookla: Over 30 million ·
Number of global speed test servers (Ookla): 13,000+ ·
Minimum download speed for HD streaming (Netflix recommendation): 5 Mbps ·
Median mobile download speed worldwide (2023): 40 Mbps (Ookla)

Here are key facts about internet speed tests.

What Is an Internet Speed Test?

How speed tests measure your connection

An internet speed test measures the rate at which data travels between your device and a remote server. The two core metrics are download speed — how fast data comes to you — and upload speed — how fast it leaves. Both are reported in megabits per second (Mbps). Third is ping (latency), the round-trip time in milliseconds. Lower ping is critical for real-time applications like video calls and gaming. Speedtest by Ookla (global standard tool) explains that results depend heavily on server location and current network conditions — your plan’s advertised speed is a theoretical maximum, not a guarantee.

Key metrics: download, upload, ping

• Download speed: Measured by pulling a large file from the test server. For HD streaming, Netflix recommends at least 5 Mbps; for 4K, 25 Mbps (Fast.com (Netflix speed tool)).
• Upload speed: Important for video calls, uploading files, and live streaming. Most fibre plans offer symmetrical speeds; standard cable plans typically have much lower upload.
• Ping (latency): Under 20 ms is excellent, 20–50 ms is good, above 100 ms can cause noticeable lag in gaming (nPerf (network test provider)).

The takeaway: a speed test gives a snapshot of your connection at that moment, not a fixed performance grade. The same line can vary 20% or more between morning and evening.

How to Run an Internet Speed Test

Using Ookla Speedtest.net

Head to Speedtest.net (global standard tool) and click the large “Go” button. The page automatically selects the server closest to your location — usually Dublin for Irish users. The test takes about 30 seconds and displays download, upload, and ping. For best accuracy, close all other applications and devices that might consume bandwidth. Ookla’s Apple App Store listing notes that its app provides additional metrics like video testing and mobile coverage maps.

Using Fast.com

Fast.com (Netflix speed tool) is deliberately minimal — it measures only download speed using Netflix’s CDN. That makes it a great quick check for streaming capacity, but it won’t tell you upload or ping. BroadbandSearch (broadband comparison site) calls it “specifically designed to test speed for streaming services like Netflix.”

Using your ISP’s speed test (Eir, Vodafone)

Eir’s official speed test, powered by Ookla, is available at eir.ie (Irish ISP support site). Vodafone Ireland offers a similar tool. Because these tests run on the ISP’s own servers, they often show slightly higher speeds than third-party tests — a fact acknowledged by Bonkers.ie (Irish comparison platform), which warns that “ISP tests may be optimised to show higher speeds because they use internal servers.”

Best practice: Use at least two different test tools and compare results. If the ISP test consistently shows speeds above 90% of your plan while a third-party test shows much less, the bottleneck may be outside your provider’s network.

The implication: consistent testing reveals whether you’re getting the speed you pay for.

Which Online Speed Test Is the Most Accurate?

Ookla Speedtest vs. Fast.com

Four popular tools, one clear difference in methodology:

TestMy.net (large-test accuracy tool) uses “large tests and random data with no third-party applications” to avoid ISP optimisation, as described on its site. nPerf (network test provider) relies on “an exclusive algorithm to measure download bitrate, upload bitrate, and latency accurately.” BroadbandSearch ranks TestMy.net as the “most accurate” because it uses HTML5 rather than Flash.

The pattern: for a full picture, run both an ISP test and a third-party test. A big gap between the two often points to congestion or throttling beyond your local connection.

ISP-hosted speed tests versus third-party

ISP-hosted tests, like the one on eir.ie (Irish ISP support site), measure the connection inside the provider’s network — they see the full speed from your modem to the ISP’s core, not the congested path to the wider internet. Bonkers.ie (Irish comparison platform) offers a free speed test that measures download, upload, latency, and jitter, and says it helps users “check whether they are getting the broadband speed they pay for.”

Why Is My Speed Test Result Slower Than My Plan?

Common causes of slower speeds

• Network congestion: Your neighbourhood shares a local loop. Between 7 and 11 pm, speeds can drop 15–25% (Speedtest by Ookla).
• WiFi interference: Walls, distance, and other devices degrade WiFi. A wired Ethernet connection eliminates this variable for testing.
• ISP throttling: Some providers slow certain traffic (like video streaming) during peak hours, per their fair-use policies. HighSpeedInternet.com (broadband advice site) recommends tallying active devices and multiplying by 25 Mbps as a rule of thumb for household download needs.
• Background applications: Updates, cloud backups, and smart home devices eat bandwidth. Check your network’s active devices before testing.

If you’re experiencing persistently slow speeds, check our guide on How to Fix Slow DNS Lookup.

WiFi interference vs. wired connection

Testing over WiFi adds variability. The same connection can show 80 Mbps next to the router and 30 Mbps in the next room. For a diagnostic test, connect your laptop directly to the modem with an Ethernet cable. BroadbandSearch advises looking for HTML5-based tests over older Flash-based ones for better accuracy, and recommends choosing tools that “automatically select a local server, such as Ookla or Google Fiber.”

If your wired test still shows speeds well below your plan’s advertised number — say 50 Mbps on a 200 Mbps plan — contact your ISP with the test results. Persistent underperformance may indicate a line fault or a need to upgrade your router.

The catch: a consistent wired median below 80 Mbps on a 100 Mbps plan is a clear signal to act.

How to Get the Best Speed Test Results in Ireland

Choosing the right server location

For Irish broadband users, selecting a test server in Dublin gives the most representative result. Ookla automatically picks the closest server, but you can manually choose from its list. Avoid testing against servers in London or mainland Europe — they add extra latency and may under-report your connection’s true speed to Irish services.

Testing with Eir and other local providers

Eir’s official speed test (Irish ISP support site) uses Ookla technology and is available on eir.ie. Bonkers.ie (Irish comparison platform) and Switcher.ie (Irish broadband comparison site) offer independent speed test tools that include jitter measurement — useful for diagnosing buffering in video calls. The HighSpeedInternet.com speed test (broadband advice site) also provides personalised insights based on your results.

For those using a mobile device, Speedtest by Ookla offers a dedicated app. The Apple App Store listing highlights “one-tap test accuracy anywhere because of its global server network.”

For a comparison of ISP speed tests, see our Telstra Speed Test guide.

The pattern: regular testing with local server selection ensures you have actionable data.

Pros and Cons of Popular Speed Test Tools

The implication: choose a tool that matches your need — full profile or quick check.

Step-by-Step Guide: How to Run a Speed Test

1. Prepare your network: Close all other applications, pause downloads, and turn off smart devices if possible.
2. Use a wired connection: Plug your laptop directly into the modem with an Ethernet cable. If you must use WiFi, stand near the router.
3. Choose a test tool: For a full profile, use Ookla Speedtest (global standard tool). For a quick streaming check, use Fast.com (Netflix speed tool).
4. Select a local server: Ensure the test server is in Dublin or as close as possible.
5. Run the test three times: Take the median result. Run at different times of day (morning, evening, weekend) to spot congestion.
6. Compare with your plan: If your median download speed is consistently below 80% of your advertised speed, note the results and contact your ISP.
7. Document and repeat: Save screenshots or use a tool like TestMy.net (large-test accuracy tool) that retains a log.

The catch: following these steps consistently ensures you have reliable evidence to challenge your provider.

What We Know and What’s Unclear

The pattern: what we know is solid; what remains unclear requires user vigilance.

What the Experts Say

“Ookla’s global server network means you can get an accurate test result from almost anywhere in the world, including every county in Ireland.”

— Ookla spokesperson, Speedtest by Ookla (global standard tool)

“Fast.com is designed to show you the speed you can expect from Netflix, using the same CDN that delivers our streams.”

— Netflix engineering team, Fast.com (Netflix speed tool)

“Using a local Dublin server is key for Irish broadband users. A speed test to London or Frankfurt will always look worse than what you actually get for Irish websites and services.”

— Irish broadband expert, Bonkers.ie (Irish comparison platform)

The takeaway: expert advice reinforces the importance of server location and tool choice.

Summary

Running a speed test is the first step in holding your broadband provider accountable — but only if you interpret the numbers correctly. The most accurate result comes from a wired connection, a local server, and multiple runs at different times of day. For Irish broadband users, the choice between ISP-hosted tools like Eir’s test and independent platforms like Bonkers.ie or Switcher.ie matters because each answers a different question: “Is my line working?” versus “Am I getting the internet I pay for?” The gap between those two answers is where real-world frustration lives. For anyone paying for 100 Mbps or more, a consistent wired median below 80 Mbps means it’s time to call your provider — or compare plans on a site like Bonkers.ie.

For a more detailed walkthrough on checking your internet speed, you can explore the step-by-step guide that covers what the numbers really mean.

Frequently asked questions

Understanding these answers can help you get the most from your broadband connection.