There can be variances from necklace to necklace in the exact sizes of the Tulsi beads. The size of the silver caps and the amount of silver in the necklace determines the size classification of the nacklace more than the size of the Tulsi itself.

Sterling Silver Tulsi Necklace Bead Length Measurement

As shown in the illustration, the silver caps are considered part of the bead when measuring bead length. So the bead length is measured from the tip of the silver cap to the tip of the opposite silver cap.