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Xfinity (Comcast) speed test

Free Xfinity speed test. Find out what % of your Xfinity / Comcast plan you're actually getting. NetStartr compares your live result against the speed you pay for.

Typical Xfinity (Comcast) delivery

~78% of advertised speed

DOCSIS 3.1 cable. Upload speeds are notoriously low compared to download — a common complaint for video creators and remote workers.

Xfinity (Comcast) plans & advertised speeds

PlanDown (Mbps)Up (Mbps)
Connect7510
Connect More20010
Fast40010
Superfast80020
Gigabit100035

ISPs advertise “up to” speeds. Your real-world result depends on line type, congestion, modem and Wi-Fi. Use NetStartr to find out what fraction you\'re getting.

How to test your Xfinity (Comcast) connection accurately

  1. Plug a laptop or desktop into your router with Ethernet (avoid Wi-Fi for the headline number).
  2. Pause cloud syncs and downloads.
  3. Open NetStartr and click Start Test.
  4. Pick your Xfinity (Comcast) plan from the “Am I getting what I pay for?” selector and read off the percentage.
  5. Re-test at peak (8-10 PM) and off-peak (8 AM) to spot congestion.

What to do if Xfinity (Comcast) underdelivers

  • Reboot your modem & router; many ISP modems re-provision on boot.
  • If you\'re under 70% of plan three days running, contact support and reference the times you tested.
  • Ask for a free modem swap (cable plans) or a tech visit.
  • If unresolved after a few weeks, request a partial bill credit.

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