How do I measure my upper arm circumference?

Measuring your upper arm circumference helps ensure that you select the correct cuff size and obtain accurate blood pressure readings. The Hilo Cuff is designed for upper arm circumferences between 22 and 42 cm; if your measurement falls outside this range, the cuff should not be used.

• A flexible measuring tape (or a string and a ruler)

• Your bare upper arm (no clothing)

1. Relax your arm
   Let your arm hang naturally by your side, relaxed and not flexed.

2. Find the midpoint of your upper arm
   Locate the middle point between:

   • The top of your shoulder (acromion), and

   • The tip of your elbow (olecranon)

3. Wrap the measuring tape around your arm

   • Place the tape around your upper arm at the midpoint

   • Ensure the tape is snug but not tight

   • It should lie flat against the skin without compressing it

4. Read the measurement

   • Read the circumference in centimetres (cm)

   • If using a string, mark the length and measure it against a ruler