Cundiff was cut by the Ravens on Sunday after he was beaten out by undrafted rookie Justin Tucker.
Gano had edged out Neil Rackers during a competition this summer, but the Redskins preferred Cundiff to him.
"I would like to thank the Redskins organization for the 3 years I spent with them," Gano wrote on his Twitter account. "I will miss my teammates and I wish you the best of luck!"
Gano tried out for the Ravens in 2009 before losing out to Steven Hauschka. Then, the Ravens got rid of a struggling Hauschka and signed Cundiff.
With the Ravens, Cundiff, 32, made 54 of 66 field goals during the last two seasons.
However, he missed a 32-yard chip shot against the New England Patriots in an AFC championship game loss. The kick, in the waning seconds of the fourth quarter, would've tied the game and almost certainly sent it into overtime.
"Billy kicked well," Ravens coach John Harbaugh said. "He could be the kicker here. He'll definitely be the kicker somewhere else. He had probably his best camp that he's ever had. So, I think he deserves a lot of credit."
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