How do I calculate the strength I need for blue light glasses?!

[Missmas]

Thinking of getting some cheap ones on Amazon for late night tv watching. My right eye is 2.25 and my left is 2.75, right eye dominant. The strengths are in 2.5 or 3. Which do I go for or should I sack the whole thing off?

I'm pretty sure they have been proven as having no affect.

Oh really? Very good to know before I swindle myself!

Quick Google...

I had some previously, wouldn't say I noticed any difference wearing them or not

Useful to know you didn't feel they did anything - think I'll leave them, thank you!