Undervalue vs Overvalue - What's the difference?

As verbs the difference between undervalue and overvalue

is that undervalue is to underestimate, or assign too low a value to while overvalue is to assign an excessive value to something.

To underestimate, or assign too low a value to.

To have too little regard for.

* Atterbury

In comparison of it I undervalued all ensigns of authority.

* Dryden

I write not this with the least intention to undervalue the other parts of poetry.

* (l)

(overvalu)

To assign an excessive value to something.