Dive computers have many benefits, which makes up for their increased cost. Following are just a few of these benefits.

When you use tables, your maximum dive time is determined by your maximum depth. This is called a "square profile," and illustrated by the chart to the left.

The truth is, most dives do not have a square profile, so your nitrogen ingassing rate changes as you change your depth. Dive computers constantly recalculate your maximum dive time by evaluating your current depth, ingassing rate at that depth, and current nitrogen levels. As a result, your maximum dive time increases when you use computers.

Dive computers automatically calculate your no-decompression limits for you. This eliminates the risk of user-error that's present when using dive tables.

At a minimum, computers contain an integrated depth gauge and bottom timer. Optional features include a thermometer and submersible pressure gauge. This reduces the number of instruments you must carry during a dive.