Houses held by lenders that may be headed for foreclosure are coming out of the shadows.

Zillow (Z), the online real estate company, said Thursday it has added information on 1.8 million pre-foreclosure and foreclosed homes to its site. The company said the homes have yet to be listed for sale and are unavailable on multiple listing services or other websites.

Visitors to and users of Apple mobile devices can search for both pre-market and for-sale homes in their area, the company said.

"Zillow is taking information that was really only available to a select group - in this case, savvy investors - and making it more easily available to interested home buyers," Spencer Rascoff, Zillow's chief executive, said in a news release. "What's more, bringing this information to light, and taking this inventory out of the shadows, can help bring these homes to market faster than ever before."

"This is another tremendous step forward in consumer empowerment," Rascoff added.

The inventory includes roughly 1.5 million homes where a lender has begun foreclosure proceedings or scheduled an auction and 250,000 homes that are owned by lenders that have not been listed yet for sale. The supply also includes roughly 147,000 homes whose owners have identified a price for which they would consider selling their home.

According to the company, visitors to can view both the company's estimate of the sale price if the home were sold at foreclosure and the amount of the discount it represents off fair market value, as well information about the loan amount, its outstanding balance and the foreclosure process.

The number of homes that could be listed for sale soon fell to its lowest level in more than three years in July, the most recent month for which data is available.