The wedding ring is traditionally worn on the ring finger, but the choice of hand varies by country and culture.

• In most countries such as the United States, the UK, Switzerland, Spain, and Italy, wedding rings are worn on the left hand's ring finger. This tradition is rooted in the ancient belief of a "vena amoris" (vein of love) running from that finger to the heart, symbolizing love and connection.

• In several European countries including Germany, Austria, Poland, Norway, Bulgaria, Lithuania, Ukraine, and some Eastern European countries like Russia and Greece, the wedding ring is customarily worn on the right hand's ring finger. The right hand here symbolizes qualities such as strength, trust, honor, and loyalty.

• In some cultures such as parts of India, the right hand is chosen because it is considered the "pure" hand used for sacred actions, further adding cultural significance to wearing the wedding ring there.

In summary, the wedding ring is most commonly worn on the left ring finger but wearing it on the right ring finger is also a well-established tradition in many countries and cultures. The specific hand often depends on cultural or religious customs as well as personal preference.

Therefore, there is no single universal hand; it depends on cultural context whether the wedding ring is worn on the left or right ring finger.