Cox speed test: check your speed and fix it
How to run an accurate Cox speed test, what a good result looks like for each plan, and what changed for Cox speeds after the move to Spectrum.
Plug a computer into the Cox gateway with Ethernet, pause other devices, and run Cox's speed test or ours three times, including once in the evening. On a wired connection you should see 80 to 100 percent of your plan's download speed. Upload is much lower on cable. Cox became Spectrum in September 2026, but existing Cox plans and speeds didn't change unless you switched.
Cox is now Spectrum: what that means for your speed
Charter, which runs Spectrum, completed its purchase of Cox on August 20, 2026, and Spectrum plans launched in former Cox areas on September 16. If you already had Cox, your plan, speed and price stayed the same. New customers, and Cox customers who choose to switch, get Spectrum's plans: Internet 100, 500, 1 Gig and 2 Gig.
How to run an accurate Cox speed test
A few minutes of setup gives a result you can trust, and one Cox or Spectrum support will accept.
- Plug in. Connect a laptop or desktop to the Panoramic WiFi gateway with an Ethernet cable. Wi-Fi results mostly measure your Wi-Fi.
- Pause everything else. Stop downloads, streaming, cloud backups and game updates on every device.
- Run the test three times. A few minutes apart, and use the middle result.
- Test in the evening too. Between 7 and 11 p.m. networks are busiest, so that result shows the slowdown you notice.
Cox's speed test vs. other tests
Cox's test at cox.com/residential/support/internet/speedtest.html uses Ookla and lets you choose a nearby server, usually on Cox's own network. Ookla Speedtest, Cloudflare and Fast.com can test to servers outside it, so they may read a little lower. Our speed test measures to Cloudflare's network. Use both: if Cox's test is fast and others are slow, the problem is often past Cox's network. Our speed test comparison explains the differences.
What a good result looks like
These are typical wired results; Wi-Fi in a far room can be much lower.
| Plan | Good wired download | Typical upload |
|---|---|---|
| Spectrum Internet 100 (Cox Advantage) | 80 to 110 Mbps | About 10 to 20 Mbps |
| Spectrum Internet 500 (Cox Premier) | 400 to 550 Mbps | About 20 to 50 Mbps |
| Spectrum Internet 1 Gig (Cox Gig) | 800 to 940 Mbps | About 35 to 120 Mbps |
| Spectrum Internet 2 Gig | 1.5 to 2 Gbps with a multi-gig port | Up to about 120 Mbps |
Upload varies by area; check the Broadband Facts label for your plan. Gig and 2 Gig plans need a computer and cable that support those speeds.
Most laptops and many routers have 1 Gbps Ethernet ports, which top out around 940 Mbps. To see more than that on 2 Gig, you need a 2.5 Gbps port on both the gateway and your computer.
If your speeds are low
Work through these before you call support.
- Restart the gateway by unplugging it for 30 seconds, then test again wired.
- Check the cable from the wall to the gateway, and remove any splitters you don't need.
- Check your Wi-Fi. If wired is fast but Wi-Fi is slow, move the gateway or add mesh. See how to boost your Wi-Fi.
- Check for an outage with is Cox down?
- Ask about your equipment. An older gateway may not support your plan's full speed; Cox and Spectrum can swap it.
- Compare plans. If you are on an old Cox plan, a Spectrum plan may be faster for the same price.
Testing on another provider? See our Spectrum speed test and Xfinity speed test guides, or why your speed test is lower than your plan.
Questions
Does Cox still have its own speed test?
Yes. Cox's speed test at cox.com still runs on Ookla's engine and lets you pick a test server. Now that Cox is part of Spectrum, Spectrum's speed test works on the same network too.
Why is my Cox upload speed so slow?
Cox runs on cable, which gives far less upload than download. Most Cox and Spectrum cable plans upload somewhere between about 20 and 120 Mbps depending on the plan, and older plans less.
What is a good Cox speed test result?
On a wired connection, 80 to 100 percent of your plan's download speed. Wi-Fi results are often half that or less, depending on the room and device.
Did my Cox speed change when Cox became Spectrum?
No. Current Cox customers kept the same plans, speeds and prices. Speeds change only if you move to a Spectrum plan.
Does Cox still have a data cap?
Spectrum plans have no data cap. If you are still on a legacy Cox plan, check your bill or account for a data usage meter.
- Cox residential speed test page; Cox Business speed test support page
- MyUtilitySearch, "Cox Internet Is Now Spectrum," September 2026 (plans, prices and upload speeds at a Destin, FL address)
- HighSpeedInternet.com, "Cox Internet Speed Test" and "Cox Is Now Spectrum," September 2026
- FOX5 Las Vegas and AZFamily, Aug 20, 2026 (merger completion)
Prices and offers change often; confirm at your address before you order. How we research
Jean founded ShopHighSpeed after trying to find one straight answer about business internet in his own town. He has been a Comcast and Verizon Fios customer, and ranks providers on what they actually deliver, not on what they advertise.