Raising tadpoles, and a half grown toad escaped in my room?

I was raising some tadpoles in a tank in my room, and all but one of them grew their legs and absorbed their tails and came onto land. I moved them all into a different land tank, but that one that was left, I moved him into a smaller bin until he was done changing so I could clean out the other tank. Well, he grew his legs and didn't absorb his tail yet, but he was sitting on the land part. I thought in a few days I could move him with the others. Then, I woke up this morning and he was gone out of the smaller bin. How can I find him? What can I do? My dog might have grabbed him, but the door was closed all night and the dog was out of the room. I'm worried he'll have dried up somewhere by now and I`ll never find him. Please help!