NCBI Front Page Taxonomy Logo
PubMed Entrez BLAST Genome Taxonomy Structure
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Taxonomy browser

Taxonomy common tree

Taxonomy information

Taxonomy resources

Genetic codes

Taxonomy Statistics

Taxonomy Name/Id Status Report

Taxonomy FTP site


How to reference the NCBI taxonomy database

How to create links to the NCBI taxonomy

How to create LinkOut links from the NCBI taxonomy

Extinct organisms

Recent changes to classification


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Linking to the NCBI Taxonomy Database

You can make the links to NCBI taxonomy browser using either organism name or taxonomy id.

The link with an organism name looks like:

The link with a taxonomy id:

The taxonomy browser displays two kinds of pages - pages that show the classification itself, and pages that show only information about a particular taxon. For a classification page, an argument lvl sets the depth of the display. So, if for example you want to display just the immediate descendants for some taxon, then you have to set lvl=1.

The default value for this argument is 3. The zero value - lvl=0 forces a taxon display page (even for internal nodes)

If you want to see the various Entrez databases' record counters on a classification page, you have to use argument p with the name of the Entrez database as an argument like p=nucleotide. Currently the following databases are supported:

Entrez databaseArgument p value
3D Domainsdomains
GEO Datasetsgds
GEO Expressionsgeo
PubMed Centralpmc
Each counter appears as a hotlink to the right of each taxon. The color of each link is the same as the color of the corresponding database check box text in the grey control area at the top of the page.

There are also links to some useful resources that can appear along with these counters. These links are also enabled using argument p and appear as named hotlinks. Currently this set includes:
Hotlink Namep valueResource description
MapViewmapviewNCBI Map Viewer presents a graphical view of several types of genomic maps
LinkOuthas_linkoutLinkOut is NCBI external weblink collection that is designed to provide users with links to a wide variety of relevant web-accessible online resources, including full-text publications, biological databases, consumer health information, research tools, and more. A list of NCBI's current non-bibliographic LinkOut providers can be found here.
BLASTgenome_blastBLAST (Basic Local Alignment Search Tool) is a set of similarity search programs designed to explore all of the available sequence databases.
TRACEtraceTrace Archive contains trace data generated by the sequencing centers and ancillary information to identify those traces.

There could be more than one argument p:

The taxon display page shows you a full lineage by default:

To display only an abbreviated lineage you have to use an argument lin=s:

And if you want to display the NCBI Taxonomy browser search page, you could use Taxonomy Browser's url without id and name argument (but you can preset other arguments for the users):

There are few parameters that are obsolete and left in place only for compatibility with older versions of Taxonomy Browser. They turn on and off display of some Entrez sequence counters:
Entrez databaseArgument name
Given value of 1 these arguments turn display of counter on while value 0 turnes it off.

These arguments could be mixed in any combination:

as well as mixed with p arguments:


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