This is the 17th most frequent Dutch word.
wel
"Wel" means "indeed," "surely," or "well" (to affirm or contrast).
In this sentence, 'wel' emphasizes certainty or affirmation in response to a potential doubt, showing the speaker assuring that they indeed know.
Ik weet het wel, maar ik vertel het je later.
I do know, but I will tell you later.
Here, 'wel' functions as a modal particle to express an unexpected or slight concession to the humor of the situation, contrasted with its importance.
Het is wel grappig, maar niet erg belangrijk.
It is indeed funny, but not very important.
In this usage, 'wel' conveys willingness or affirmation about coming to the event, given the stated condition is met.