The opposition says the information being used for the rating tool is out-of-date and has caused distress for older Australians.
The system ranks aged care providers from one to five, with providers given a three-star rating considered acceptable, four stars listed as good, and two as needing improvement.
Ms Wells lashed the coalition over its criticism, saying they would not know transparency if "they looked through a window" and saying the opposition was trying to take the sector back "into darkness".
"The data is absolutely not inaccurate," she told the ABC on Tuesday.
"Sunshine is the best disinfectant and this is the first time Australian families have ever had the opportunity to see this kind of data and feedback about residential aged care facilities."
Ms Wells said more than 60 per cent of the data used for the rating system was independent, and included surveying aged care home residents to record their experiences and gauge the quality of care for particular facilities.
"I'm ambitious for aged care, I don't want three stars ... to be the ceiling ... I want three stars, an acceptable standard, to be the floor," Ms Wells said.
"I want to lift the standard of aged care in Australia, but we can't improve what we can't measure, and that's why our star rating ... is a vital part of that process."
The government's plan to increase wages in the sector gradually over 18 months has been slammed by the Health Services Union.
In its submission to the Fair Work Commission, the government proposes a phased salary increase, with the first stage to fund a 10 per cent increase starting in July next year, with a further five per cent increase from mid-2024.
Health Services Union national president Gerard Hayes labelled the plan a "devastating" move that would "crumble" the workforce.
"Three quarters of aged care workers have already indicated they will quit aged care in the next six months unless there is a serious pay rise," he said.
"What is the Federal Government's plan to prevent a complete collapse? Send in the army, again?"
Opposition aged care spokeswoman Anne Ruston said the government was delivering the sector a broken promise by delaying the pay rise.
"Labor talked a big game ahead of the last election, but now that they are in government, they are proving time and time again that their words were all for the headlines," she said.
"The Labor government must deliver the full pay rise to aged care workers, as they promised."
