Using Your Hand as a Ruler

Hand as measurement tool (adapted from Wikipedia)

If you’ve ever needed to measure the width of a box but have no ruler, here’s a handy (literaly) tip: just use your hand as a measuring tool.

• 1 inch = width of thumb
• 3 inches = width of four fingers of the palm closely pressed together
• 9 inches = outstretched span of hand (from thumb to little pinkie)

This idea shouldn’t strike you as strange. Indeed, historically, people measured lengths with units derived from the human body:

• Cubit
  The length of the forearm from the elbow to the tip of the middle finger. For the average adult, this translates to 18 inches or slightly less than 46 cm.
• Span
  An outstretched hand of an adult. The length from the tip of the thumb to the little pinkie is a span. Two spans make a cubit. In the average adult, this is about 9 inches or slightly less than 23 cm.
• Handbreadth or palm
  The width of four fingers closely pressed together. Typically 6 adult handbreadth or palm makes a cubit. This is about 3 inches or almost 8 cm.
• Foot
  Yep, it’s the length of a foot – which came to be defined as 12 inches (which was the length of King Henry I’s foot). The average Caucasian person’s foot length is actually about 9.4 inches.

Obviously, your hand may yield a different result. So take 30 second taking measurements of your hand. Who knows when it’ll come in … handy!