Easyfig is a Python application for creating linear comparison figures of multiple genomic loci with an easy-to-use graphical user interface. It allows BLAST comparisons between multiple genomic regions, ranging from single genes to whole prokaryote chromosomes, to be generated, visualized, and interactively coloured, enabling a rapid transition between analysis and the preparation of publication quality figures. Easyfig is freely available under a GPL license for download from the SourceForge website. It is platform independent and can be used on Mac OS X, Unix, and Microsoft Windows. It requires no Unix or scripting knowledge, making it accessible to biologists with little or no bioinformatics or computing experience. The graphical user interface permits images to be drawn with minimal user input, yet allows highly customizable figures to be generated for closer analysis or publication. Easyfig accepts multiple sequences with or without annotation in standard formats, such as GenBank and EMBL. It can handle a variety of loci lengths, from full prokaryote genomes down to individual loci or genes. The relative orientation of each region can be specified, and features such as tRNAs, coding sequences, or user-specified features can be added. Features can be coloured via the GUI or according to annotation file information. Genomic regions can be aligned left, right, centered, or directly perpendicular to their best BLAST hit. A 'zoom' feature enables subregions of large sequence files to be specified and examined in more detail. The figure can also show custom graphs displaying guanine-cytosine content, read coverage, or a user-defined graph. BLAST comparisons between two or more loci can be generated by the Easyfig interface if BLAST+ or legacy BLAST is available. Alternatively, previously generated tabular comparison files can be loaded into Easyfig. The Easyfig interface allows customization of the minimum expect values, lengths, and identities of BLAST hits to be displayed in the final image. Hits are coloured on a gradient according to the BLAST identity value. Inverted matches can be shown using a different colour gradient. The colour scheme, gradient settings, and height in pixels of the alignment can also be defined by the user. Identity and scale legends can be embedded in the image along with specific annotations such as a scale bar and a colour gradient representing the identities of the BLAST hits. Figures generated by Easyfig are saved in compressed bitmap or vector graphics format at a user-defined resolution. A command-line version of Easyfig is also available, enabling it to be incorporated into analysis pipelines. Funding was provided by the National Health and Medical Research Council of Australia and the Australian Research Council. No conflict of interest was declared.Easyfig is a Python application for creating linear comparison figures of multiple genomic loci with an easy-to-use graphical user interface. It allows BLAST comparisons between multiple genomic regions, ranging from single genes to whole prokaryote chromosomes, to be generated, visualized, and interactively coloured, enabling a rapid transition between analysis and the preparation of publication quality figures. Easyfig is freely available under a GPL license for download from the SourceForge website. It is platform independent and can be used on Mac OS X, Unix, and Microsoft Windows. It requires no Unix or scripting knowledge, making it accessible to biologists with little or no bioinformatics or computing experience. The graphical user interface permits images to be drawn with minimal user input, yet allows highly customizable figures to be generated for closer analysis or publication. Easyfig accepts multiple sequences with or without annotation in standard formats, such as GenBank and EMBL. It can handle a variety of loci lengths, from full prokaryote genomes down to individual loci or genes. The relative orientation of each region can be specified, and features such as tRNAs, coding sequences, or user-specified features can be added. Features can be coloured via the GUI or according to annotation file information. Genomic regions can be aligned left, right, centered, or directly perpendicular to their best BLAST hit. A 'zoom' feature enables subregions of large sequence files to be specified and examined in more detail. The figure can also show custom graphs displaying guanine-cytosine content, read coverage, or a user-defined graph. BLAST comparisons between two or more loci can be generated by the Easyfig interface if BLAST+ or legacy BLAST is available. Alternatively, previously generated tabular comparison files can be loaded into Easyfig. The Easyfig interface allows customization of the minimum expect values, lengths, and identities of BLAST hits to be displayed in the final image. Hits are coloured on a gradient according to the BLAST identity value. Inverted matches can be shown using a different colour gradient. The colour scheme, gradient settings, and height in pixels of the alignment can also be defined by the user. Identity and scale legends can be embedded in the image along with specific annotations such as a scale bar and a colour gradient representing the identities of the BLAST hits. Figures generated by Easyfig are saved in compressed bitmap or vector graphics format at a user-defined resolution. A command-line version of Easyfig is also available, enabling it to be incorporated into analysis pipelines. Funding was provided by the National Health and Medical Research Council of Australia and the Australian Research Council. No conflict of interest was declared.