The actress and country singer, 37, posed in jeans and covered her breasts with her arm in an official debut on Instagram Thursday.
"This next chapter, this next me is free," she began.
The mom of Jace, 2, and Jolie, 5, also told fans that she's finding love again — with herself.
"I'm ready to be in love with myself, and that includes my body," she wrote.
The One Tree Hill alum added that although she doesn't know what her next steps will be, she "was good enough before, and I'm good enough now."
"I am grateful to all of you who have helped me find my strength. No one can take it away from me again," Kramer wrote.
Tori Spelling shared kind words to Kramer in the comments section.
"Love you for finding your beautiful inner voice. We are all grateful for your strength. You inspire all of us moms! Love you mama. Xo," the Beverly Hills, 90210 star, 47, said.
"So here goes. After many years of consideration I have decided to get a breast augmentation and lift. I want to be open about WHY. First off, because 'I' want to. That right there should be enough, but I feel like I need to explain the 'I' part," she wrote.
Jana Kramer/instagram Jana Kramer
The country singer went on to share that she had previously considered having plastic surgery "with everything that happened" in her marriage, but this time she chose it for her. (Caussin admitted to having multiple affairs before entering treatment for sex addiction in 2016.)
The timing of the breast implants, Kramer has admitted, was "interesting" considering her divorce.
The actress gave a "boob update" earlier this month when she went to visit her plastic surgeon, Dr. Jacob Unger, for her last checkup during what he called the "worrying period" post-procedure.
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Dr. Unger examined Kramer's chest and told her she appeared to be "healing beautifully" before asking how she felt about her new, enhanced bosom. Kramer said: "I'm actually really happy about them. Interesting timing, but I'm happy about them."
Earlier this week, Kramer candidly opened up about her divorce.
On Monday's episode of her podcast Whine Down, she said, "I'm just waiting for when they say it gets better but in the meantime, it's definitely been hard."
Todd Williamson/E! Entertainment/NBCU/Getty Mike Caussin and Jana Kramer
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Kramer continued, "The hardest part is when you imagine something and you work for something and the rug gets pulled from underneath you. You're just kind of left there on the floor spinning. Divorce sucks."