When choosing a chain length for necklaces, chains for bars, suspended discs and pendants are going to be slightly different.
When measuring for a pendant necklace, you’re only measuring the actual chain, as the pendant hangs below the chain itself. Suspended disc and bar necklaces are a little different because the discs and bars don’t hang below the chain. For this reason, when ordering suspended disc and bar necklaces, you’ll want to account for the fact the entire length of the necklace—bar length/disc diameter, jump rings, chain, clasp, and all—is included in the chain measurement.
For example, let’s say you’re ordering a 17’’ long bar necklace, and that the bar measures 2’’ long. This really means that the chain is 15’’ long, with the bar accounting for the remaining 2’’. If you want your disc or bar to rest a bit lower on your neck, you may want to consider choosing a slightly longer chain or ordering an extender.