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.
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 and Wi-Fi 6 routers require 12V (or 19V for Asus gaming routers). Never plug 12V into 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 start streaming 4K video or downloading large files.
Most TP-Link and Netgear routers use 2.1mm center pins. Asus routers often use 2.5mm. If the plug feels wobbly, do not use it.
Related Calculators & Checkers
DC Barrel Connector Finder
Filter DC coaxial barrel plugs by outer/inner diameter (OD/ID) with live cross-section diagram.
DC Polarity Checker & Decrypter
Verify Center Positive (⊕) vs Center Negative (⊖) symbols and avoid instant reverse-polarity blowouts.
Voltage Calculator & Cable Drop
Calculate voltage mismatch tolerance (±5% rule) and DC wire resistance drop over distance.
Current & Splitter Load Sizer
Size adapters with the 80% continuous duty safety rule and sum multi-device splitter loads.
CCTV Power Supply Calculator
Calculate power box amperage for 4/8/16-channel security cameras and IR night-vision current spikes.
USB-C PD & Fast Charge Checker
Validate USB Power Delivery 3.0/3.1 profiles (5V-48V EPR), Samsung 45W PPS, and 5A cable needs.