This page contains a partial list of representative major databases and search engines useful in an academic setting for finding and accessing articles in academic journals, or in repositories, archives, or other collections of scientific and other articles. As the distinction between a database and a search engine is unclear for these complex document retrieval systems, see:

the general list of search engines for all-purpose search engines that can be used for academic purposes

bibliographic databases for information about databases giving bibliographic information about finding books and journal articles.

Note that "free" or "subscription" can refer both to the availability of the database or of the journal articles included. This has been designated as precisely as possible in the lists below.

General

BASE (free index to academic content, mainly free)

Cambridge Scientific Abstracts (subscription-based database aggregator)

EBSCO (subscription index to subscription articles in a variety of fields)

Google Scholar (free index to mostly subscription articles)

GoPubMed (It is a knowledge-based search engine for biomedical texts with social networking)

Ovid Technologies (subscription-based collections and indexes)

ProQuest (subscription index to subscription articles)

ScienceDirect (index to subscription articles)

Scirus (free index to academic web content)

Scitation

Scopus (subscription-based index to journal articles, web content, patents, etc.)

Sens Public (databases, journals, other web content in social sciences, art and philosophy (several languages))

Web of Science (subscription-based database aggregator)

Windows Live Academic (free index)

Publisher or platform-specific

Blackwell Synergy (subscription-based collection)

Atypon Link (Platform for various publishers: subscription-based collection)

HighWire (Platform for various publishers: subscription-based and free collection)

IngentaConnect (Platform for various publishers: subscription-based collection)

JSTOR (Backfiles of many major journals; subscription-based collection)

MetaPress (Platform for various publishers: subscription-based and free collection)

SpringerLink (subscription-based and free collection)

Non-English language

Japanese databases:

CiNii (Japanese National Scholarly and Academic Information Navigator) CiNii in Japanese CiNii in English

NDL (Japanese National Diet Library Collection) NDL in Japanese NDL in English - mainly covers the best-known Japanese publishers and journals

Open access journals

Directory of Open Access Journals (free collection and index)

LivRe! (free list of journals)

Open J-Gate (free collection of articles)

Specific subjects

Agriculture

CAB Direct (platform hosting CAB Abstracts and Global Health, subscription-based databases for agriculture and environment), produced by CABI.

Technology

IET Inspec (physics, electrical engineering, electronics, communications, control engineering, computers, computing, information technology, manufacturing, production and mechanical engineering)

IEEE IEEE Xplore (electrical engineering, computer science, and electronics)

ACM (Computer science and engineering)

U.S. DOE - Energy Citation Database

Natural sciences, mathematics and computer science

ADS (Astrophysics Data System) (free index to astrophysics, geophysics and physics journals and conference proceedings)

arXiv (free index to free articles)

CiteSeer (free index to free and subscription-based articles)

Current Index to Statistics

Libra (Academic Search) (object level search engine, more reasonable ranking)

SPIRES (free index to all the literature of particle physics - most articles are free via arXiv but it also indexes subscription journals and conferences)

The Collection of Computer Science Bibliographies (free)

MathSciNet (a nearly complete index of mathematical journals maintained by the American Mathematical Society)

Social sciences

ERIC (Educational Resource Information Center) (free index to subscription articles on education)

LISA (Library and Information Science Abstracts)

NBER (free index to subscription articles in economics)

RePEc (free index to partly free articles in economics)

SSRN (free index to mostly free articles in the social sciences)

Medicine

PubMed (free index to free and subscription articles)

HubMed (free alternative interface to PubMed)

EMBASE (Biomedical and pharmacological database)