Most papers that are free-to-read are available thanks to “green OA” copies posted in institutional or subject repositories. The fact these copies are available for free is fantastic because anyone can read the research, but it does present a major challenge: given the DOI of a paper, how can we find the open version, given there are so many different repositories?
The obvious answer is “Google Scholar” :) And yup, that works great, and given the resources of Google will probably always be the most comprehensive solution. But Google’s interface requires an extra search step, and its data isn’t open for others to build tools on top of.
We made a thing to fix that. Introducing oaDOI:
We look for open copies of articles using the following data sources:
oaDOI was inspired by the really cool DOAI. oaDOI is a wrapper around the OA detection used by Impactstory. It’s open source of course, can be used as a lookup engine in Zotero, and has an easy and powerful API that returns license data and other good stuff.