Internet shorthand for "Got to go". Also, it can mean "good to go", depending on the context.
Good to go:
"Say, I'm heading out. You coming?"
"gtg."

Got to go:
"Shoot, it's almost midnight. gtg."
by Mephianse September 9, 2004
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when you don't have the time to write a long bye.
by kel December 10, 2003
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Means gotta go. But it has evolved into something more like i dont wanna txt you anymore
Person: Whats up?
Person 2: Nothinnnn.
Person:hey gtg bye
by personthatsubmits stuff September 1, 2010
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Good to go.

Commonly confused with 'g2g' which means "got to go". They are different, and 'gtg' is normally used in online games to indicate a participant's "ready status." It is seeing common usage today as indicating in the example.
"Are you ready to hit the clubs? I'm gtg!"
by kohner March 20, 2009
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Good to Go. Can mean leaving or having to go. In military slang it is similar to acknowledged.
"Sergeant, we are rolling out at zero-shit-thirty" "Good to go Sir (gtg). I will pass word"
by wertyy102 October 25, 2016
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