How Long Will a UPS Run a Wi-Fi Router and Modem?

Answer
2h 43m 600VA UPS · 20 W

A Wi-Fi router plus a cable or fiber modem draws only about 20 W, so even a small 600VA UPS (1 × 12 V 7 Ah battery) keeps your internet up for about 2h 43m. A 1500VA UPS lasts about 8h 25m.

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W
Sum of connected equipment.
W
Optional: 0 to skip.
V
Two 12 V batteries = 24 V.
Ah
%
Runtime
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How we calculated this

    For estimating and educational purposes only. Results are approximate and are not a substitute for a licensed professional, the manufacturer's instructions or your local code. Disclaimer

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    Router and modem runtime by UPS size

    UPSBattery15 W20 W30 W
    600 VA1 × 12 V 7 Ah battery3h 50m2h 43m1h 40m
    1,000 VA2 × 12 V 7 Ah batteries8h 47m6h 13m3h 50m
    1,500 VA2 × 12 V 9 Ah batteries11h 53m8h 25m5h 10m

    Mesh systems and routers with 4G backup can draw 30 W or more. Check the watts on the power adapter label.

    Frequently asked questions

    Is a UPS worth it for a router?

    Yes. It keeps Wi-Fi, VoIP phones and cameras online through short outages and protects the router from surges.

    Can I use a power bank instead?

    Only for routers that run on 12 V DC, with a 12 V output cable or a DC UPS. Those small DC UPS units are very efficient for routers.

    Open the full calculator: UPS Runtime Calculator →