For rings, you can measure your finger size by yourself.
At TimJeweler, we offer extra small to extra large bracelet sizes (US):
5.5 inches for extra small wrists(kids, teenager);
6.5 inches for small wrists;
7.5 inches for regular wrists;
8.5 inches for large wrists;
9.5 inches for extra large wrists.
HOW TO MEASURE
STEP 1: Measure your wrist with a flexible tape measurements or a strip of paper just below the wrist bone, where you would normally wear the bracelet.
STEP 2: If you are using a plain strip of paper, mark your size with a pen or pencil then use a ruler to measure the length, and give your wrist a loose fit to move around.
Necklace Size Chart
To clean, wipe with soft cloth. Avoid frequent contact with water and strong chemicals, such as detergent, bleach, perfume, etc. Store in a jewelry box or soft cloth.