_images/logo.png provides simple-to-use REST web services to query/retrieve gene annotation data. It’s designed with simplicity and performance emphasized. A typical use case is to use it to power a web application which requires querying genes and obtaining common gene annotations. For example, services are used to power BioGPS.

What’s new in v2 API

  • ALL species are supported now! That’s more than 14,000 in total. [more]
  • Gene annotation data are even more up-to-date (weekly updates).
  • Gene query service supports “fields” parameter to return any fields. Previously, you need to call gene query service separately if you need more than gene symbols and names.
  • Fine-tuned query algorithm to return relevant gene hits first.
  • Our query backend is more scalable and extensible. Ready to expand more annotation data as we go.

Migration guide from v1 to v2 API

Still want to stick with v1 API for a while? It’s still there: v1 API, but annotation data there won’t be updated any more.

Quick start provides two simple web services: one for gene queries and the other for gene annotation retrieval. Both return results in JSON format.

Gene query service




View nicely formatted JSON result in your browser with this handy add-on: JSON formater for Chrome or JSONView for Firefox.

To learn more

Gene annotation service



<geneid>” can be any of valid Entrez or Ensembl Gene ids. A retired Entrez Gene id works too if it is replaced by a new one.

To learn more

How to cite

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