Tuesday, May 17, 2016

Bracelet Length Calculator - Bracelet Sizing

Have you ever made a bracelet, and when you were all finished, it was either too snug or too loose?

Here is a guide that will help making bracelets that will fit. It is especially important for bracelets that have a certain thickness, such as beaded kumihimo bracelets, bracelets with large beads and any other types of bracelet are not flat like a measuring tape. 

Step 1. Before making the Bracelet, you need the following:

1. Wrist Size
Measure with a flexible measuring tape at the place where yo want to wear the bracelet. This will also work for an anklet.  

2. Type of Fit

Tight Fit - Do not add anything
Snug Fit - Add 1/4“ to 1/2” (0.25" to 0.50") / 0.6 cm to 1.25 cm
Comfort Fit - Add 1/2“ to 1” (0.50" to 1") / 1.25 cm to 2.5 cm 
Loose Fit - Add 1“ to 1 1/4” (1" to 1.25") / 2.5 cm to 3 cm

3. Bead or Braid Diameter/Bracelet Thickness

That's the measurement between the inner and the outer circumference. 

Step 2. Wrist Size + the Type of Fit Adjustment = Inner Circumference

Now we need to calculate the Middle Circumference. That's the bracelet length.

The math is all Pre-Algebra Yikes that was a long time ago...

Circumference = π x Diameter
Diameter = Circumference / π
π = The Number Pi = 3.14

From this, we can deduce the following:
Inner Diameter = (Wrist Size + Type of Fit) / π 
Middle Diameter = Inner Diameter + Bracelet Thickness 
Middle Circumference = π x (Inner Diameter + Bracelet Thickness)
Difference between Inner Circumference and Middle Circumference = π x Bracelet Thickness
So the adjustment for the bracelet thickness is as follows:
Adjustment for Bracelet Thickness = Bracelet Thickness multiplied by Pi
Adjustment for Bracelet Thickness = Bracelet Thickness x 3.14

Step 3. Calculate the Bracelet Length = Middle Circumference

Bracelet Length = Wrist size + Type of Fit + Braid Thickness multiplied by Pi
Do the multiplication first and use 3.14 for Pi, that’s close enough or use the calculator below.

Bracelet Size Calculator

Enter all the input numbers in inches (decimal form) or in centimeters. The calculator work either way. 

If you enter the Bracelet Thickness only, you will get the extra length to add to the wrist size to adjust for the bracelet thickness. Add to that the type of fit. 

Then of course if you are making a kumihimo bracelet with a clasp, take the clasp length in consideration. 

In the Kumihimo Bracelet with Long Magatamas and C-Lon Tex 400 Bead Cord shown above, the magnetic clasp covered by a peyote sleeve is 1 inch/2.54 cm long. Braid a first short section with no beads that will be wrapped and glued into the clasp. Braid the beaded kumihimo section. Then another short section with no beads for the other end of the clasp. The braid is 0.38"/0.96 cm thick, so the adjustment for the bracelet thickness is 1.19"/3.02 cm. Minus the clasp from that and you get 0.19"/0.48 cm. So make the beaded section just a tad longer (0.19" - that's a 3/16"  or 0.48 cm longer) than the wrist size adjusted for the type of fit desired. The clasp length will make up the difference. 


This chart shows average sizes for both women and men.

Standard Bracelet Sizes

I recently got an email asking me how long a beaded braid section needed to be for one of my kumihimo bracelet kits. After really pondering on this question, I had to write this post and create the online bracelet length calculator. I hope this will help you for your next bracelet! - Marion

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