Krona allows hierarchical data to be explored with zoomable pie charts. Krona charts can be created using an Excel template or KronaTools, which includes support for several bioinformatics tools and raw data formats. The charts can be viewed with a recent version of any major web browser (see Browser support).
Krona works best in Firefox

Publication

• Ondov BD, Bergman NH, and Phillippy AM. Interactive metagenomic visualization in a Web browser. BMC Bioinformatics. 2011 Sep 30; 12(1):385.

Examples

• Miscellaneous
  • Nutrition facts for granola
  • Disk usage for a folder
• Metagenomics
  • RDP classification of 16s reads from Moving pictures of the human microbiome [Caporaso et al.]
    • Taxonomic abundance of skin microbiome samples for 4 consecutive days, with optional coloring by classification confidence
    • Comparison of taxonomic abundance in skin microbiome samples from two individuals on the same day, with optional coloring by RDP Library Comparison significance values
  • PhymmBL classification of MetaHIT human gut sample MH0072 [Qin et al.]
    • Taxonomic abundance, colored by classification confidence
  • METAREP vertical profile of South Pacific Gyre bacterioplankton [Pham et al.]
    • Taxonomic abundance, based on BLAST hits
    • Functional abundance, based on EC (Enzyme Commission) numbers of annotations
  • MG-RAST classification of acid mine drainage biofilm metagenomes [Tyson et al.]
    • Taxonomic abundance
    • Functional abundance

Tools that use Krona

• metAMOS - metagenomic assembly pipeline
• MGTAXA - metagenomic taxonomy prediction server
• Metavir - viral metagenomic annotation server
• PhymmBL - metagenomic fragment classification
• MG-RAST - metagenomics analysis server

Features

• Animation

  • Krona uses HTML5 to create animated transitions when zooming in and out.

• Portability

  • Krona charts are explored with web browsers, so no installation is necessary to view them as long as an Internet connection is available.
  • Since Krona charts use HTML5, they will work without plugins using any modern browser and on any operating system.
  • Each Krona chart is contained in a single file, making them easy to share.

• Flexibility

  • Krona can create charts from XML, and charts can contain custom HTML with links to other pages. This allows straightforward integration with custom applications.
  • The use of web technologies makes it easy to include Krona charts in existing web pages.
  • Krona can render SVG snapshots for printing or publication.

Help

• [Browsing Krona charts]

• Creating Krona charts

  • [KronaTools] - a set of scripts to create Krona charts from several Bioinformatics tools as well as from text and XML files.
  • [ExcelTemplate] - allows Windows and Mac users to create charts from custom data within Microsoft Excel (Excel 2011 required for Mac).

• [Discussion]

• [How to cite]

Updates