Preparing the ruler
Print this page
Without scaling, at 100%.
Double-check scale
Fold the ruler
By measuring against a standard mm
ruler, or the credit card diagram below.
Along the dotted line.
Credit card length
0
10
20
30
40
50
60
70
80
90
100
5
15
25
35
45
55
65
75
85
95
95
85
75
65
55
45
35
25
15
5
Using a friend
FOLD
FOLD
90
80
70
60
50
40
30
20
10
0
Using a mirror
100
For step by step instructions go to https://www.eyebuydirect.com/guides/pd-ruler-guide
or scan this QR code with your mobile devices camera