What does Image Compression Quota mean?

Hi,

Thanks for contacting us here about this extension.

What does Image Compression Quota mean? What effect does is have? Quota per what? Day/week/month?
Can you please clarify.

It's important for me to decide what plan to buy.

Yes, that means you will have a 1GB or 3GB quota corresponding to your ordered Speedcache package.

https://www.joomunited.com/products/speed-cache#prices

That's the total amount of image size optimized on your site. And it will be valid in a year.
Please go here for more information:

https://www.imagerecycle.com/prices


Hope it helps!
Kind regards,