Stop testing.
Start watching.

SpeedWatch monitors, grades, and diagnoses your broadband over time — not just once. Know exactly what's going on, in plain English.

Install for Chrome
✓ No account required ✓ No tracking or ads ✓ 100% free & open source
🔬 Powered by M-Lab — Google-backed open internet measurement 🌍 Used by researchers and regulators worldwide

Everything you need to understand your broadband

Not just a speed number. A complete diagnosis of your internet connection.

⚡

Speed Testing

M-Lab NDT7 powered. Choose Quick, Balanced, or Thorough test modes depending on what you need.

🩺

Connection Diagnostics

Get an A–F health grade covering packet loss, bufferbloat, and latency stability — with plain English explanations of what it means.

🔄

Automatic Monitoring

Schedule tests to run automatically. Get alerts when speeds drop below your threshold. Runs quietly in the background.

📈

History & Trends

Full test history with trend charts. See peak vs off-peak performance and spot patterns your ISP won't tell you about.

📄

ISP Accountability

Compare actual speeds against what you're paying for. Export evidence for complaints or Ofcom.

🔒

Privacy First

All data stored locally by default. No tracking, no ads, no accounts. Built on open source test infrastructure you can verify.

🌐

Community Data

Opt in to share anonymised results and help build a real picture of UK broadband performance — area by area, ISP by ISP.

Why SpeedWatch?

Other speed tests show you a number. SpeedWatch shows you a diagnosis.

A

Health Grading (A–F)

Your connection gets a grade based on real TCP diagnostic data — download, upload, latency, jitter, packet loss, and bufferbloat.

🔧

Engineer-Grade Data

The same metrics network engineers use to diagnose problems — presented in plain English anyone can understand.

💡

Not Just Speed — Why

Know why your video calls drop. Know why gaming lags at 8pm. SpeedWatch explains the cause, not just the symptom.

How it works

Up and running in under 30 seconds.

1

Install

Add SpeedWatch from the Chrome Web Store. One click, no account needed.

2

Test & Diagnose

Run your first test — or let auto-monitoring handle it. See diagnostics explaining why your connection behaves the way it does.

3

Track & Export

Monitor trends over time. Export evidence when you need to hold your ISP accountable.

The broadband accountability gap

51%

Of UK households don't get the speeds they're paying for

£100+

Average annual overpayment for underperforming broadband

14 days

Typical wait to get an engineer visit that often finds "no fault"

Frequently Asked Questions

Quick answers to common questions and troubleshooting tips.

Speed test results vary depending on the test server, its location, the testing methodology, and network conditions at that moment. SpeedWatch uses M-Lab or Cloudflare servers — both are reliable but may give slightly different numbers to, say, Ookla (Speedtest.net). This is normal. For the most consistent comparison, use the same provider and test at similar times.
Two common reasons: 1) You have community sharing disabled — enable it in Settings. 2) A VPN was detected during the test — VPN-flagged results are automatically excluded from community data to maintain accuracy.
Open SpeedWatch, go to the Settings tab, and update the postcode field. Press Save Settings. Your new postcode will be used for future community comparisons.
Go to chrome://extensions, find SpeedWatch, and click Details. Scroll down and click Clear data. This removes all local data including test history and settings. Alternatively, uninstall and reinstall the extension.
  • Storage — To save your test results, settings, and history locally.
  • Alarms — To run scheduled speed tests in the background.
  • Notifications — To alert you when a scheduled test completes or if an outage is detected.
  • Identity — Used for optional cloud sync features (sign in with Google).
  • Host permissions (Cloudflare, M-Lab, ipinfo.io) — Required to run speed tests and detect your ISP/location.
A few things to check:
  • Are you connected via Wi-Fi? Try moving closer to your router or using a wired connection.
  • Is a VPN active? VPNs add overhead and reduce measured speeds.
  • Are other devices or tabs using bandwidth? Downloads, streaming, or video calls can affect results.
  • Try switching test provider (M-Lab vs Cloudflare) in Settings to compare.
  • Run a few tests at different times — a single test is just a snapshot.

Help & Getting Started

Everything you need to get the most out of SpeedWatch.

🚀 Running Your First Test

Click the SpeedWatch icon in your toolbar, then press Run Test. The test takes around 15–30 seconds and your results appear immediately.

SpeedWatch measures download, upload, ping (latency), and jitter — giving you a complete picture of your connection.

🩺 Understanding Your Health Grade

Fast doesn't always mean good. SpeedWatch analyses TCP-level diagnostics to assess packet loss, bufferbloat, latency stability, and congestion.

These are combined into an A–F health grade with plain-English explanations of any issues detected.

📊 What the Diagnostics Mean

  • 🔌 Line quality issue — High packet loss suggests a faulty cable, poor Wi-Fi, or ISP fault
  • 🚦 Network congested — Can't fully use available bandwidth, often worse at peak hours
  • 📡 Bufferbloat — Speed is fine but latency spikes under load
  • 📶 Unstable connection — Latency varies wildly, affecting real-time apps
  • 📉 Below expected speed — You're not getting what you're paying for
  • ✅ Healthy — Low packet loss, stable latency, minimal bufferbloat

⚙️ Tips & Settings

  • Set your postcode in Settings to see community comparisons for your area.
  • Enable scheduled tests to monitor your connection automatically.
  • Export data as CSV or JSON for ISP complaints or your own analysis.
  • VPN detection flags VPN results and excludes them from community data.

🔒 Privacy & Your Data

Your data stays on your device by default. Nothing is shared unless you explicitly opt in.

Stored locally:

  • All speed test results and history
  • Your settings and preferences
  • Your postcode

Shared only if you opt in:

  • Speed and latency results
  • Postcode (area only)
  • ISP name

Never shared: your name, IP, account details, or browsing data.

Changelog

v1.4.1 — 17 March 2026

  • Jitter-based Mobile Detection — detects hotspot usage via latency variance analysis when ASN detection is inconclusive.

v1.4.0 — 15 March 2026

  • Scheduled Automatic Testing — background speed tests at your chosen interval (15 min to 24 hours) on home networks.
  • Daily Test Cap — 100 tests per 24 hours to ensure responsible M-Lab usage. Counter shown in the Run Test button.
  • Mobile Connection Detection — detects UK mobile carriers (EE, Three, O2, Vodafone + MVNOs) and flags tethered connections.
  • Home Network Awareness — 🏠 warning when not on your home network. Non-home results display live but don't save to history.
  • VPN Detection Overhaul — residential-first approach with ~40 UK ISPs. Only flags positive VPN signals.
  • Cleaner Chart Tooltips — plain text labels, no emoji icons. Sidepanel legend uses coloured text instead of boxes.
  • CSV Export — added geolocation (browser postcode) and mobile connection columns.
  • Pre-flight Checks — tests won't start if you're offline. Better error messages for server timeouts.
  • UI Auto-refresh — results from scheduled tests appear automatically without reopening.

v1.3.0 — 15 March 2026

  • Side Panel Mode — expand icon in popup header opens SpeedWatch in the browser side panel.
  • Auto-detected Postcode — no more manual entry; location detected via browser geolocation.
  • First-run Disclaimer — new users see accuracy notes about Wi-Fi and shared networks.
  • Home Network Filtering — analysis only includes tests from your home network.
  • Ping Prominence — ping/latency gets its own dedicated display alongside download and upload.
  • Privacy Page Rewritten — clear explanation of M-Lab data flow and what SpeedWatch collects.
  • "Home Networks" — renamed from "Trusted Networks" throughout for clarity.

v1.2.0 — 11 March 2026

  • Browser Geolocation — auto-detect your location via Wi-Fi positioning, verified via Postcodes.io.
  • Postcode Verification — manually entered postcodes validated against Postcodes.io.
  • Location Status Display — see which location method was used after each test.
  • Richer Community Data — verified coordinates, ward, and district for better analytics.
  • Cross-check Warning — alert if detected location differs from saved postcode.

v1.1.0 — 10 March 2026

  • Full Postcode Support — community data uses your full postcode for precise area reporting.
  • GA4 Analytics — anonymous usage analytics.
  • Connection Health Grade — NDT diagnostics with retransmission, bufferbloat, and RTT analysis.

v1.0.0 — 7 March 2026

  • One-click speed tests (download, upload, latency, jitter)
  • Cloudflare and M-Lab NDT7 support with Quick/Balanced/Thorough presets
  • History, trends, CSV/JSON export
  • ISP detection with VPN flagging
  • Scheduled background monitoring
  • Privacy-first: no accounts, no tracking cookies

Stop guessing. Start diagnosing.

Install SpeedWatch and find out what's really happening with your broadband.

Install for Chrome

Need help? support@app-factory.dev