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Research metrics

A guide to identifying and analysing research-related metrics, with support material and further guidance.for related tools

Other tools

This page summarises some other large multidisciplinary bibliographic databases. UCL does not have a subscription to any of these, but you may find them useful as alternative tools for your research.


Lens is a citation database of scholarly papers and patents, including links between them. It offers a structured search functionality similar to Web of Science or Scopus, but with some variations. It includes the ability to search with regular expressions as well as filter by subject based on text classification.

It covers around 250 million articles, but the algorithmic basis of the system means that there may be some duplication, and there may be less detailed indexing than in Scopus or Web of Science. It offers a simple set of metrics but no normalised or complex metrics.

Access is free for the general public or "individual users for public-good and non-profit uses". UCL does not have an institutional subscription.


OpenAlex is a large free bibliographic database, with around 250 million items. It is the successor to Microsoft Academic Graph, and includes a broader range of material than Scopus or Web of Science, but a more limited search function. The level of metadata varies; for example, it cannot currently identify review papers, and does not distinguish articles from preprints. It is in rapid development as of 2024, and data quality is expected to improve over time.

One major advantage is that it is geared towards large-scale export of bibliographic data; up to 100,000 records can be exported at a time, and the underlying dataset is available for download. It may thus be particularly useful for large-scale offline analyses.

Access is free to all users.


Dimensions is a large bibliographic database, with around 140 million items, of which about 75% have searchable full text. Searches can be carried out against the full text or against the title/abstract, and results can then be filtered and exported in a similar way to Scopus or Web of Science.

A set of citation metrics and other analysis functions are provided, and individual articles have more detailed citation metrics including normalised citation indicators (the field citation ratio and relative citation ratio).

Dimensions is a subscription service and UCL does not have a subscription, but an individual user account can be registered for free. This allows access to the basic search and analysis functions, but only a limited set of filters and analysis views. A subscription is also required to access patent, dataset, grants, and clinical trials data.