On Sun, 16 Dec 2018 05:49:18 -0800 (PST), Nancy2
> wrote:

>All I do is whack around the edge of the lid with the handle of a heavy stainless table knife, and
>then give it a good thump right in the center, and it is easily opened...or at least easy enough
>for my strength (which is lessening). It doesn't interfere with any leak-proof abilities of the lid.
>
>Or you can whack the lid's edge on a sturdy countertop, turning the jar as you go. That
>works, too. No need to buy any kind of device.
>
>N.

For me with the occasional obstinate jar lid a rubber glove
works first time every time, don't even need to put it on your hand,
lay it over the cap to give a non slip grip.