Drill shopping gets confusing fast because every box shouts a bigger number. The useful way to compare is by three specs: maximum torque (in-lb or Nm), chuck size, and the battery platform you are already invested in.
Voltage is a platform, not a power rating
An 18V/20V MAX drill and a 12V drill can both drive screws all day. Higher voltage usually means more torque and longer runtime, but a modern brushless 12V tool often outperforms an old brushed 18V one. Compare torque figures, not just volts.
Torque: how much twist you actually get
For cabinet and light assembly work, 250–400 in-lb is plenty. Framing, decking, and lag screws want 500 in-lb and up, usually from an impact driver rather than a drill. If a listing only gives a vague 'powerful', look for the number elsewhere on the page.
Chuck size and bits
Most drills use a 1/2-inch keyless chuck, which takes the widest range of bits. 3/8-inch chucks are lighter and fine for bits up to about 3/8 inch. If you plan to use hole saws or auger bits, go 1/2 inch.
Brushless or brushed
Brushless motors run cooler, last longer, and squeeze more runtime from a pack. For daily professional use the premium is worth it; for occasional home jobs a brushed drill is a reasonable saving.
Buy into one battery platform
Batteries and chargers are the real cost. Choose a platform with the tools you will add later — impact driver, reciprocating saw, light — then buy bare tools instead of new kits.
Browse power tools or start with the first toolkit guide.