Value of Polish and Danish coins

Where can I find value of Polish and Danish coins in the 1970's 1980's and before?

Welcome to the site.

https://www.ngccoin.com/price-guide/world/
On there fill in at least the first three boxes marked with a * and any other boxes as needed ...



which (for a quick example) as I have this coin ...

I entered Denmark / All Regions / 25 Øre and then also 1972 which brought up this page >
https://www.ngccoin.com/price-guide/world/denmark-25-%C3%B8re-km-855.2-1972-cuid-1045868-duid-1237512