Step 1 : Introduction to the question "How many amendments does the U.S.Constitution have in total?"
The Constitution of the United States, which entered into force in 1789, is the oldest written national constitution in use. The framers of the U.S. Constitution included a provision whereby the document may be amended, generally (though not solely) by a two-thirds majority of each house of Congress followed by ratification by legislatures in three-fourths of the states. Since 1789 the Constitution has been amended 27 times; of those amendments, the first 10 are collectively known as the Bill of Rights and were certified on December 15, 1791.