"I fully complied by every rule I was governed by," Clinton said in her first public comments since it was disclosed last week that she exclusively used a private email and server for government business.
In a 20-minute news conference, Clinton described her decision to rely on her private account as a matter of "convenience" and a way to avoid carrying two devices. She said she had never used her personal email to discuss any classified information.
Clinton said her server would remain private. She also said she had discarded thousands of personal emails, such as communications related to her daughter's wedding or her mother's funeral, but she insisted she had given the State Department all relevant emails.
"Everything that would be in any way connected to work is now in possession in the State Department," Clinton said. Her email practices have raised questions about whether she fully complied with federal laws requiring government officials to preserve written communications involving official business. Republicans have said Clinton avoided transparency and committed an ethical lapse.
The controversy has upended Clinton's careful blueprint for the rollout of her 2016 presidential campaign. The clear front-runner for the Democratic nomination, Clinton had planned to spend March touting her work on women's issues and giving a handful of paid speeches before announcing her candidacy in early April.
Clinton tried to stick to that plan in the days following revelations that she relied on her private email for government business and controlled her communications on her own server. But as criticism from Republicans mounted and Democratic allies started publicly pushing Clinton to address the matter, her team hastily arranged Tuesday's brief news conference.
Clinton spoke shortly after delivering remarks at a women's empowerment event at the United Nations. She then made her way to a nearby hallway where dozens of reporters and photographers were awaiting her first formal news conference since leaving the State Department in early 2013.
Before the question-and-answer session, Clinton's only comment on the matter had been a late-night tweet last week saying she wanted the State Department to the release her emails.
Clinton served as the nation's top diplomat throughout President Barack Obama's first term. In late 2014, nearly two years after she left the administration, she turned over 55,000 pages of emails to the State Department in response to an agency request.
The department says it will take several months to review the material. Spokeswoman Jen Psaki said today that once the review is complete, the emails will be posted online for the public to see.
Passages revealing anything from trade secrets to sensitive national security information could be redacted, in keeping with Freedom of Information Act guidelines.