How to Measure magnification
How can I see how strong a magnifying glass is?

I bought this magnifying glass Wholesale Magnifying Glass With Free Shipping From China Distributor and I want
to know how to test it to see how strong it is. I hear a lot of people talk about
magnifying and how strong the magnification is, but I would like to know the true
magnification of my magnifying glass. I have a few of them and some seem stronger then
others. How can I rate these? How can I pin a correct number on mine? How do the companies
that make these come up with these numbers.