how many delegates signed the constitution?

Thirty-nine delegates signed the United States Constitution on September 17, 1787. Out of the 70 delegates chosen to attend the Constitutional Convention, 55 actually attended, and of those present at the signing, 38 out of 41 signed the document, with a few refusing to sign for various reasons. John Dickinson did not attend the signing but authorized another delegate, George Read, to sign on his behalf, making the total number of signers 39.