How to measure my astigmatism diopters?

Hi everybody,

this might seem like a stupid question but I have never measured my astigmatism diopters. I didnt even know I had a small astigmatism - I saw a blur but I could not distinguish between the normal blur and astigmatism blur.

I started using app which was given to me by kem and when I go away from the Astigmatism wheel, I can see all lines being the same at a further distance than even 2 weeks ago.

I know that Jake has a way to measure astigmatism but I dont understand it too well and I dont have the paper clipper and other things that are needed.

I do have a test lens kit though.

I know how to measure my diopters with the use of a cm measurement and also Snellen. That is pretty clear to me. But is there any way how to measure my astigmatism?

I also wanna measure the astigmatism of my son as Im sure he was overcorrected.

Thank you,


I made that nice little device and glued it onto a board - but it doesn’t do anything for me. The astimatism wheel shows darker and lighter lines, but this device is a mystery to me.

thank you shaerah for your reply. I do astigmatism wheel too and that is great to work out, which axis I have that is weaker/stronger.

But I would like to calculater diopters as well.

If Jake’s tool is confusing, have you tried the suggestion lower on the page in that blog post - # 2 Astigmatism (Without Tools)?

Did you see this post from @Astigmatism_Assasin?

If your trial lens kit includes a Jackson cross cylinder lens, you can try that. Have you read in the Working Group on Astigmatism Guide? There is an appendix with instructions on using the JCC lens for measuring.

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oh I have not seen Astigmatism - Assassin´s post, I will read through it. Thank you!

Hi Shaerah, i will try the system what is described by Astigmatism Assassin.

Im not sure if i have the Jackson lens.

Here is the description of the Lens kit i have. Maybe the Jackson lens has another name as well?


last but one on the list
JCC = Jackson cross cylinder = cross cylinder

ok, so I dont seem to have that Jackson thingy there :unamused: