De or het hypotheekberekening?

The correct Dutch article is:

de hypotheekberekening

Rule Words ending in -ing: almost always de. See the rule

How to use hypotheekberekening

the hypotheekberekeningde hypotheekberekening
this hypotheekberekeningdeze hypotheekberekening
that hypotheekberekeningdie hypotheekberekening
our hypotheekberekeningonze hypotheekberekening
your hypotheekberekeningjouw hypotheekberekening
every hypotheekberekeningelke hypotheekberekening
which hypotheekberekening?welke hypotheekberekening?
a big hypotheekberekening / the big hypotheekberekeningeen grote hypotheekberekening, de grote hypotheekberekening