Circa gives you the power to create beautiful circos plots without writing a single line of code

Circa is desktop software (for Mac, Windows, and Linux) that allows you to make circos plots from your genomic data. You can load in genomic data, construct a circos plot, export as a PNG (image) and SVG (for publication), and save your session for later to continue constructing the perfect circos plot. Any type of genomic data with chromosome names and positions can be plotted with Circa.

Watch how you can make this complicated bacterial comparative genomics plot in just 5 minutes

Let’s compare Escherichia coli and Salmonella tiphymurium by gene homology:

Ideal data for plotting in Circa includes variant calls, copy number profiles, and any genomic features like repeats, genes, or the plethora of data available in ENCODE or through the UCSC genome browser. Any file where the data is in rows and headers will work, including but not limited to: CSV, TSV, BED, BEDPE, VCF (specially parsed to expand the INFO field), and GTF.

Here’s a simple 1-minute circos plots showing variants in a human genome


Circa can plot any genomic data from any organism and any reference genome. All you have to do is give Circa a file that says how long the chromosomes are. Files for human reference genomes hg19 and hg38 are included in Circa’s starter pack. It also includes instructions for getting chromosome names and sizes from other species through the UCSC genome browser.

There is no limit to the number of tracks or datasets you can plot in Circa.

You can add multiple plots on top of each other. Each track can contain multiple layers, which means you can put a scatter plot and a line chart on top of each other, and it will automatically rescale to accommodate both datasets. You can also set multiple horizontal lines, so thresholds like y=0, y=100, and y=1000 can be set with different colors. If you need vertical lines, you can use a rectangle layer to draw them, making it easy to draw several at once.

Several ways to plot your data

Circa screenshot circos plot types

Save and share your Circa plots

You can share circa plots with other people. When you save a plot, it generates a .circa file that includes everything your collaborator needs to see and edit the plot in Circa on their own computer. Just like Word or Photoshop files, if your colleague also has Circa on her computer, she can edit your plot, add data to it, restyle it, and export new images.

Flexible styling of plot elements

You can specify the chromosome colors however you like, using the easy color picker or by entering a list of HEX codes. When you have the perfect color scheme, you can copy the list of Hex codes as text to quickly apply the same colorscale to other figures in your paper.

Circa changing colors of circos plot

In addition to a set of nice-looking defaults, you can also pick the colors for all the chromosomes individually. You can invent a whole new color scheme and save it as a list of Hex codes for later.

Data file requirements

Data files you load into Circa must be smaller than 10 MB and be in a neat row and column format where columns are separated by tabs, commas, or spaces. Each file must have a header in the first row that you will use when deciding which columns to plot, and there must be columns corresponding to chromosome names and positions. VCF files are also supported (must have .vcf extension). Check the input file format tutorial for an in-depth walkthrough of the supported file types.

Export as PNG or SVG

PNG (.png) is a simple image format that can be opened with any image-editing application. Use this for the first submission to a journal or for sharing results in a talk.

SVG (.svg) is a specialized format that can be opened and edited with applications like Adobe Illustrator or Inkscape. It is a vector format, so the resolution is infinite. This is what journals often want to see for final submissions and will make your figure look crisp no matter how far people zoom in.

Learn more about Circa

Circa gallery of circos plotsCheck out the Circa tutorials

How to buy Circa

When you have watched the tutorials and are confident that Circa is the right software for your research needs, click the big button below to buy Circa. This gives you a 1-person license that you can use forever. If you need multiple licenses of Circa for different people in your lab or organization, you can increase the quantity during checkout using the “+” button.

When you buy Circa, you will get immediate access to download Circa for Mac, Windows, and Linux operating systems. You will also get a Starter Pack of example input files, including the chromosome name and size files for human hg19 and hg38, which you will need to start a Circa plot. These are the same “genome” files you need for bedtools, and are very simple to make. The starter pack also includes instructions about how these files were downloaded from the UCSC genome browser, so you can use Circa for any organism you are working on.

If you have any questions about Circa, check out the FAQ and tutorials.

Ready to make beautiful circos plots from your own data? Click here to buy Circa