Router & Modem Adapter Checker
Lost your Wi-Fi router power brick? Routers require strict voltage regulation (typically 12V or 9V DC, Center Positive). Test if your spare power adapter will keep your network running reliably without crashing under load.
Router Label Specs
Look at the sticker on the bottom of your router
Spare Adapter Specs
Read the OUTPUT label on the power brick
💡Common Router Power Supply Traps
Older single-band routers frequently ran on 9V DC. Modern dual-band, Wi-Fi 6, and Wi-Fi 7 routers require 12V (or 19V for Asus ROG gaming units). Never supply 12V to an old 9V router!
If you use a 1.0A adapter on a 1.5A router, the router may boot up but crash or reboot as soon as multiple phones stream 4K video or download large files.
Most TP-Link and Netgear routers use 2.1mm center pins. Asus routers and Orbi mesh nodes use 2.5mm pins. A 2.1mm plug will not fit onto a 2.5mm pin, while a 2.5mm plug on a 2.1mm pin fits loosely and causes intermittent dropouts.
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