1000 Mbps fibre: cable, WiFi and real speed

Practical guide

The contracted speed and the result measured by one device are not exactly the same. Results vary with cable or WiFi, the device, distance from the router, walls, interference and simultaneous network use. Spain’s CNMC publishes the national framework for telecommunications service quality, while Ofcom explains common factors that affect WiFi.

What the contracted speed means

It is the nominal access capacity under the service conditions. A test from a phone, laptop or television also reflects the limits of that device and the local network.

How to test over cable

1. Connect a compatible device directly to the router by cable.
2. Pause downloads, backups and video on other devices.
3. Repeat the test at different times and record the device, connection and time.

What changes over WiFi

Distance, walls, interference, device compatibility and local traffic can reduce the speed received by one device. A single WiFi test therefore does not represent the line capacity on its own.

When to ask for support

Contact technical support with your service reference, whether the test used cable or WiFi, the device and the time. To request the featured residential offer, select I WANT IT.

Editor: Cloudwifi, S.L. · Reviewed: 14 September 2026 · Technical sources: CNMC and Ofcom, checked 14 September 2026