November 30, 2022

OverDrive API Usage Indicates Growth of Ebook Checkouts via OPAC


141017_OverDriveAPIOverDrive is currently processing 350 million API server calls per month, and has supported 1.3 million checkouts via APIs to date in 2014, according to internal data given to LJ. API use has also risen steadily each quarter, with almost 233,000 checkouts during the first three months of the year, more than 529,000 in Q2, an estimated 692,000 in Q3, and a projection of at least 1 million during the final three months of the year.

The volume of activity can be attributed partly to the integration and use of OverDrive’s APIs by third-party vendors. The company made available its metadata, search, and availability APIs two years ago, and its content and patron authentication APIs, which enable vendors to streamline the checkout experience within an app or OPAC, were released during the fall of 2013. The market is still taking shape, but this usage data (provided by OverDrive in an infographic format) is beginning to yield insights into how patrons are accessing ebooks and other content when there are multiple different options for discovery and download.

Leading library app provider Boopsie—which had been working with OverDrive on integration efforts prior to the release of any of the APIs—currently leads all third-party vendors in OverDrive API traffic. Boopsie is followed by three integrated library system vendors—SirsiDynix, Polaris Library Systems, and Innovative Interfaces Inc. Open source library resource portal VuFind is fifth, thanks in part to the integration work performed by Colorado’s Marmot Library Network.

One outcome of API integration is that 16 percent of OverDrive ebooks are now borrowed directly from library OPACs. An additional three percent of API traffic comes from other third-party vendors, such as app providers. Together, this accounts for 19 percent of OverDrive’s total traffic. The top five city or county library systems leading API traffic are Minnesota’s Hennepin County Library, New Jersey’s Monmouth County Library, the Los Angeles Public Library, the Greater Phoenix Digital Library, and the Seattle Public Library. For state and regional consortia, the Ohio Digital Library led API traffic, followed by My Media Mall in Illinois, the Ontario Library Service Consortium, the Wisconsin Public Library Consortium, and the Washington Digital Library Consortium.

API traffic will likely continue to build as additional vendors complete integration efforts and users find that they have new options for discovering and downloading OverDrive content. For now, OverDrive’s own app remains the preferred avenue for access by a considerable margin, with 56 percent of OverDrive’s library traffic originating there. Meanwhile, 25 percent of the company’s traffic originates from an OverDrive-powered library website.

Discussing the data with LJ, OverDrive Director of Marketing David Burleigh said that one of the messages that the company had gotten from customers and from The Readers First initiative was that while OPAC integration would help libraries resolve a few specific problems, the ultimate goal was to expose more potential readers to content, and different users prefer to search for and access content in different ways.

“A lot of requests and interest in having the experience go through the library [OPAC or app] was absolutely valid, and all of the vendors, including us and others made this happen,” Burleigh said. “What we’re finding with ebooks is that there are other ways people want to do it, too.” Burleigh pointed to OverDrive’s recently announced partnerships with the Huffington Post, Buzzfeed, and to embed samples of ebooks in online reviews and news stories and encourage readers to check their local library for the title.

“That’s what we’re finding,” said Burleigh. “Our role is to make it happen, to make it work efficiently, but also find new ways to engage and find new readers.”

Matt Enis About Matt Enis

Matt Enis (; @matthewenis on Twitter) is Associate Editor, Technology for Library Journal.