We are not kidding. The width of the credit card is about the same as the width of a standard size lens (also defined as ‘M’ or ‘medium’ size) and can be a perfect tool to help in this situation.
In only three steps you will know your size using your credit card
1. Take your card
Take a Credit card, its width is approximately the same as the width of a standard size lens (also defined as ‘M’ or ‘medium’ size) and it may be a perfect tool to help you in this situation.
2. Get the nearest mirror
Stand in front of the mirror, place one edge of the card at the centre of your nose and observe the place where the other edge ends. If the card ends at the end of your eye, you should go for standard size (M).
3. Finally put it under your eye
If it extends beyond the end of your eye, then your fit is small (S). If the card, on the other hand, does not even reach the end of your eye, your size is large (L). That’s it. Fast and easy.