When was the Declaration of Independence ratified by the thirteen colonies?

it was approved by the house on , July 4, 1776

and signed on August 2, 1776

The Lee Resolution claiming independence was adopted (congress does not ratify its own resolutions) on 7/2 in closed session of the Continental Congress (2d). (There was no House and Senate.) The Declaration, explaining the rationale, was adopted by the congress on 7/4. It was published with that date and first read publicly in Philly with the ringing of the Liberty Bell on 7/8. As the Declaration was what was generally published, the folks at that time used the date they saw. The document had to be ratified by the "colonies" and formal signing began on 8/2. I do not know the procedure for ratification.

The Continental Congress turned into the Confederation Congress or the Congress of the Confederation with the Articles of Confederation. They wrote the US Constitution and so we got what we now have as just "Congress," a House and a Senate.

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