Best battery backup for a Wi-Fi router, and how long it runs
Buy the CyberPower AVRG900LCD if your router and modem plug into the wall. It is $139.95 at Amazon. It keeps a router and modem (about 20 watts together) on for roughly 2.4 to 3 hours.
If your router runs on a 5, 9 or 12 volt adapter, the Pecron D77 mini UPS does it for less money and runs about 2.6 to 3.3 hours.
Our pick for each job
- Router and modem plug into the wall
CyberPower AVRG900LCD$139.95 at Amazon - Router runs on a 5, 9 or 12 volt adapter: lowest price
Pecron D77 mini UPS$59.90 at Amazon - Router and modem both on 12 volt adapters: more battery
TalentCell SL3400 mini UPS$64.99 at Amazon - Longest run, or a mesh system and fiber box
CyberPower CP1500AVRLCD3$199.95 at Amazon
Each pick follows a stated rule. Best overall is the lowest-priced plug-in unit that runs a 20 watt router and modem at least 2 hours on an aged battery. The lowest-priced mini UPS, the one with more battery and the longest run follow the same way, from the listing prices and battery sizes below.
How many hours of Wi-Fi each one gives you
Hours = battery watt-hours × the share you can use ÷ the watts your equipment draws. Find your row by adding the watts printed on your router’s and modem’s power adapters. Each range runs from an older battery (80%) to a new one.
| Unit | 10 W One router | 20 W Router and modem | 30 W Mesh system or gateway, plus a fiber box |
|---|---|---|---|
| CyberPower AVRG900LCD 108 Wh battery, 47.52–59.4 Wh usable | 4.8–5.9 h | 2.4–3 h | 1.6–2 h |
| CyberPower CP1500AVRLCD3 216 Wh battery, 95.04–118.8 Wh usable | 9.5–12 h | 4.8–5.9 h | 3.2–4 h |
| Pecron D77 76.96 Wh battery, 52.33–65.42 Wh usable | 5.2–6.5 h | 2.6–3.3 h | 1.7–2.2 h |
| TalentCell SL3400 97.2 Wh battery, 66.1–82.62 Wh usable | 6.6–8.3 h | 3.3–4.1 h | 2.2–2.8 h |
Usable watt-hours: for a mini UPS, 85 of every 100 Wh in the battery reach your router; the converter loses the rest2. For a plug-in UPS, 55 of every 100 Wh do, from Wirecutter’s test of the CyberPower LE1000DG: a modem and router (up to 20 W) ran 3 hours on its 108 Wh battery1. A plug-in UPS also uses a few watts of its own, so its 10 W hours are the top of its range. A modem alone measured 12.4 W idle and 14.6 W under load7; our load ranges put a router and modem together at 15 to 40 W.
Plug-in UPS or mini UPS?
A plug-in UPS takes your router’s and modem’s own plugs, so there is nothing to match. It costs more per hour of runtime and is larger. A mini UPS sits between the wall and your router and feeds its round DC plug. It is smaller and cheaper per hour, but your router’s adapter has to match the mini UPS’s voltage and plug. Check the small print on the adapter before you buy.
Worked example. A modem that draws 12 W and a router that draws 8 W use 20 W together. The Pecron D77 holds 76.96 Wh. After the converter’s loss, 65.42 Wh reach the router. 65.42 Wh / 20 W = 3.3 hours. With an older battery, plan on 2.6 hours.
Already own a power station?
Plug your router and modem into it. The EcoFlow DELTA 2 Max (1,727 usable Wh) runs a 20 watt router and modem about 46 hours. See the best power station for home backup. You do not need a UPS as well.
Every unit compared
Each row is one product Amazon sells now, matched by the maker’s model number. Battery sizes come from the maker’s data or the Amazon listing.
| Unit | Battery | Plugs | Best for | Amazon |
|---|---|---|---|---|
| CyberPower AVRG900LCD Plug-in UPS (AC) | 108 Wh3 One 12 V 9 Ah sealed lead-acid battery | 6 battery-backup outlets, 6 surge-only | Any router and modem that plug into the wall. No adapters to match. | $139.95 at Amazon |
| CyberPower CP1500AVRLCD3 Plug-in UPS (AC) | 216 Wh4 Two 12 V 9 Ah sealed lead-acid batteries | 6 battery-backup outlets, 6 surge-only | A mesh system, a gateway and a fiber box, or a router plus a few other small devices. | $199.95 at Amazon |
| Pecron D77 mini UPS Mini UPS (DC) | 76.96 Wh5 76.96 Wh lithium battery | 5 V, 9 V and 12 V round DC plugs, a PoE port and a USB-A port | A router or modem that runs on a 5, 9 or 12 volt power adapter. | $59.90 at Amazon |
| TalentCell SL3400 mini UPS Mini UPS (DC) | 97.2 Wh6 97.2 Wh lithium-ion battery | Four 12 V round DC plugs (9 to 12.6 V), one 9 V plug and two USB ports; up to 37 W | A router and a modem or fiber box that both run on 12 volt adapters. | $64.99 at Amazon |
Prices checked November 1, 2026; we keep no price history.
Questions people ask
How long will a battery backup run my Wi-Fi router?
A router and modem together draw about 20 watts. At that load the CyberPower AVRG900LCD runs about 2.4 to 3 hours, the Pecron D77 mini UPS about 2.6 to 3.3 hours, and the CyberPower CP1500AVRLCD3 about 4.8 to 5.9 hours. A router alone, at about 10 watts, runs about twice as long.
Do I need to back up the modem too?
Yes. A router with no modem has nothing to send your traffic through. If you have fiber internet, the fiber box (the ONT) is the modem, so plug it in too. Add up the watts printed on every power adapter you back up.
Will my internet work if my provider loses power?
Your Wi-Fi stays on, and your internet works as long as your provider's own equipment has power. If the provider's network is down, you still have home Wi-Fi for local devices.
Can I use a regular computer UPS for a router?
Yes. A computer UPS such as the CyberPower AVRG900LCD works the same way. Plug the router and modem into the outlets marked as battery backup. A big UPS spends more of its battery on its own electronics at small loads, so a mini UPS goes further per watt-hour.
Will a mini UPS fit my router?
It fits if your router's power adapter says the same voltage (5, 9 or 12 V) and the plug is the same round DC plug. The Pecron D77 mini UPS has 5, 9 and 12 V plugs; the TalentCell SL3400 mini UPS has 12 V and 9 V plugs. Read the small print on your router's adapter, then pick the output that matches.
Should I use a power station instead?
Use one if the outage is about more than Wi-Fi. The EcoFlow DELTA 2 Max runs a 20 watt router and modem for about 46 hours, and it can also run a fridge or a CPAP. For Wi-Fi alone, a UPS costs far less.
Sources
- CyberPower press release on Wirecutter's test of the LE1000DG (via Webull), read October 28, 2026
- Racks and Watts: DC mini UPS for a router and fiber box, read October 28, 2026
- CyberPower AVRG900LCD specifications (Etilize data sheet), read October 28, 2026
- CyberPower CP1500AVRLCD3 specifications (Cables Plus USA), read October 28, 2026
- Amazon listing: Pecron D77 mini UPS, read October 28, 2026
- Amazon listing: TalentCell SL3400 mini UPS, read October 28, 2026
- The Tested Hub: ARRIS SURFboard SB8200 review (plug-in meter), read October 28, 2026
Related: how long outages last where you live · best power station for home backup · how much power small devices use · safety rules.
CyberPower AVRG900LCDRouter battery backup
$139.95 at Amazon