On Mar 18, 6:35*am, Jim Elbrecht wrote:
I know what size I need-- and I can try these on to see if they work
for me--

But I have 100 or so glasses of varying magnifications and I want to
sort and label them.

Is there an easy/cheap method of measuring magnification?

Web searches are just turning up pages telling me how to figure out
what strength I need. *I want to know what strength I *have*.

Thanks
Jim

Obviously there's some details missing here.

If, as you say, " I can try these on to see if they work for me..."
then aren't those the only ones you need to know the magnification
off? Find all of the ones that work for you, take them to any store
that sells reading glasses and follow the instructions on how to
choose the mag power you need. Once you know that number, it should be
the same as the ones "that work for you".

Now, if you want to label all of them so you can donate them in an
organized manner, then I say "Good for you, that's nice!"