The Nature Index tracks the affiliations of high quality scientific articles published in 68 science journals independently chosen by the scientific community as the journals scientists would most like to publish their best research in. Updated monthly, the Nature Index presents research reports of approximately 9,000 parent institutions worldwide presenting a page of output statistics for each institution along with information on institutions collaborating with the institution in the publication of Index articles. Each of the approximately 60,000 articles in the Index has a dedicated article page with social and mainstream media coverage tracked by Altmetric. League tables of output of institutions can be generated on the fly on a global, regional or country basis and by broad subject area as well as by article count and fractional article count. Compare with other metrics of science (e.g., Impact Factor, h-index), Nature Index is the prominent scientific journal ranking with global reputation on original natural science and life science research.