Best Tool Battery Inverters (DeWalt, Milwaukee, Makita)
Updated Oct 20, 2026 Β· 3 picks Β· Prices checked Oct 15β20, 2026
If you already own cordless tools, you already own a stack of emergency batteries. A tool battery inverter snaps onto an 18V or 20V pack and turns it into a 120V outlet for small loads like a fan, a lamp, a router, a laptop or a phone charger. They are quiet, fume-free and safe indoors, but small: these run about 175 to 300 watts, so they will not run a fridge, microwave or space heater. The waveform matters. Our top pick, the MillerTech 300W, puts out a pure sine wave and works with DeWalt, Milwaukee or Makita batteries, which makes it the better choice for a CPAP or sensitive electronics. The Milwaukee M18 TOP-OFF and DeWalt DXAEPIP2W are cheaper, modified sine options for phones, laptops, fans and lights.
β Top Pick
MillerTech 300W Pure Sine Power Tool Battery Inverter
Why it's herePure sine 120V output from DeWalt 20V/FLEXVOLT, Milwaukee M18 or Makita LXT batteries, so it is the safer choice for CPAPs, laptops and other sensitive electronics. 300W continuous with low-voltage cutoff to protect the battery, and a 1-year warranty.
No independent review used. Two versions at $144: DeWalt/Milwaukee and Makita; pick the one for your batteries. Cannot charge tool batteries. Verified Oct 19 2026.
~$144Price checked Oct 20, 2026at store.ldsreliance.com
β‘ Modified sine wave inverters (the Milwaukee and DeWalt picks) can struggle with CPAPs, some laptops and other sensitive electronics. Use a pure sine model like the MillerTech for those, check your device manual, and keep loads under the rated watts.