Diagonal Leg Span - Measuring Your Tarantula

In the United States, Diagonal Leg Span (DLS) is the standard measurement for tarantulas. This involves measuring from the tip of the front leg (leg 1) to the tip of the back leg (leg 4) on the opposite side, typically noted in inches and increments of 0.25" or 0.125".

In other parts of the world, keepers often use Body Length (BL), measuring from the eyes to the spinnerets, and the metric system. Another way to track a tarantula's growth is by counting their molts, each known as an instar.

Small spiderlings from genera like Cyriocosmus and Kochiana usually measure around 0.125" DLS. These tiny spiders can be fed fruit flies or small, pre-killed crickets. Larger spiderlings, such as those from Pamphobeteus and Theraphosa, start around 1" DLS.

For reference, you can compare certain coins to DLS measurements:

• 0.75" DLS: about the size of a penny
• 1" DLS: about the size of a quarter
• 1.5" DLS: about the size of a silver dollar

A grain of rice, measuring about 0.25", can be used to estimate the size of smaller spiders.

We often include free rulers with our packages to help you monitor your tarantula's growth!