Dial calipers look similar to a vernier caliper, but feature an easy-to-read display dial instead of a vernier scale. Dial calipers also feature a rod at the bottom of the scale that can measure depth. One drawback is the toothed rack on which the dial is mounted that runs down the side of the scale. If debris gets into the rack, it could push the calipers out of calibration.
Digital calipers have an easy-to-read electronic display for inside, outside, and depth measurements. Considered the fastest, most efficient caliper type, they save time by eliminating the need to guess between values. The display can also switch between inch and metric units, lock at a value for later reading, and reset to zero from any position. Some models also feature a data port to send measurements to a computer or printer.
Vernier calipers use a measurement scale that’s more granular than simply metric or inches. The vernier scale is so precise that it gives measurements between the points on a standard scale. Of course, this can make your measurements difficult to read if you don’t have a dial or digital display. But a standard vernier does have sturdier jaws and is, in general, more rugged since it doesn’t have any internal moving parts.