The duration of a laser hair removal treatment session can vary depending on several factors, including the size of the treatment area, the technology and equipment used, and the individual's specific needs. Here are some general guidelines for the typical time required for different areas:

1. Small Areas: Small areas like the upper lip, chin, or underarms can often be treated in as little as 10-15 minutes per session.

2. Medium Areas: Medium-sized areas like the bikini line or lower legs may take around 30-45 minutes per session.

3. Large Areas: Larger areas like the back or full legs can range from 45 minutes to 1.5 hours or more per session, depending on the individual's hair density and the type of laser technology used.

It's important to note that multiple treatment sessions are usually required to achieve the best and most long-lasting results. The sessions are typically spaced a few weeks apart to target hair in different growth cycles effectively.

Additionally, the duration of the session may be influenced by the speed of the laser technology used. Some modern lasers offer fast repetition rates, allowing for quicker treatments.

The best way to determine the expected treatment time for your specific needs is to consult with a qualified practitioner. They can assess the treatment area, your individual hair and skin characteristics, and provide you with a more accurate estimate of the time required for your laser hair removal sessions.