How do I determine the correct length for my Guinand strap?

So that you can order a suitable bracelet for your watch - be it when purchasing the watch or as a replacement strap - you should know your wrist circumference. There are several ways you can measure the circumference of your wrist. Take a measuring tape, string, or tape and place it around your wrist. The measured dimension is your wrist circumference in cm or mm or inch.

The values for

  • optimal wrist circumference in mm or inch
  • minimal wrist circumference in mm or inch
  • maximal wrist circumference in mm or inch

are calculated using the following formula:

Bracelet length (mm) or (inch) + dimension between the bracelet bars (mm) or (inch) - "play" (mm) or (inch) = wrist circumference (mm) or (inch)

  • Strap length for minimal wrist circumference: innermost hole for clasp
  • Strap length for maximum wrist circumference: extreme hole for clasp
  • Strap length for optimal wrist circumference: middle hole for clasp
  • Play (takes into account the height of the clock): typically around 12 mm / 0,472 inch


Watch: Flieger Chrono
Leather strap: Rally type

Strap length of the Rally strap (middle clasp hole): 145 mm / 5.71 inch
Dimensions between the strap bars for the Flieger Chrono model: 45 mm / 1.77 inch
Play: 12 mm / 0,472 in

145 mm + 45 mm - 12 mm = 178 mm wrist circumference (optimal)
5.71 inch + 1.77 inch - 0,472 inch = 7.01 inch wrist circumference (optimal)