What was the outcome of the Battle of Verdun?
Basically nobody really won!
In total Germans and French lost during the battle about
Also, for both the contenders was a battle that decimated their armies without giving a decisive victory for the outcome of the war.
The initial idea of the German commander in chief Falkenhayn was to nail down the French in a position they were forced to defend at any cost (for reasons of historical and of national pride, the fortress of Verdun) and in doing so get bled to death loosing as many soldiers as possible (battle of attrition), annihilate their army and possibly be forced to sue for peace.
The French, under Petain, were forced to defend every inch of ground suffering terrible casualties. The horror of the battle was magnified by the extensive use of poisonous gasses, flamethrowers and, obviously, extensive and devastating use of artillery that basically created a "moon" landscape on Earth!
At the end nobody really "won" as we are used to think of a normal battle: the Germans were repelled and went back to their starting trenches but the "victorious" French paid a terrible price, that greatly damaged their army, to defend a place that was, basically, strategically useless.