Clinton was resting at home after being discharged Wednesday from New York Presbyterian Hospital, where she was being treated for a blood clot on her brain, State Department spokeswoman Victoria Nuland said Thursday.
"Some of the senior staff who spoke to her ... say that she's sounding terrific, upbeat, raring to go," Nuland said.
Clinton is looking forward to returning to the office and "is very much planning to do so next week," Nuland said.
The spokeswoman said she didn't know when Clinton would return.
Clinton also remained committed to testifying before Congress about the attack on the U.S. Consulate in Benghazi, Libya, Nuland said.
"[We] are working with the committees on an appropriate set of dates," she said.
In December, a stomach illness forced Clinton to cancel her appearance on Capitol Hill. She suffered a concussion when she fainted after becoming dehydrated from the bug, her office said.
Clinton, 65, checked into New York Presbyterian Hospital Sunday with a blood clot, which apparently developed after her fall and concussion. She was treated with blood thinners during her hospital stay and was expected to make a full recovery, doctors said.