UCSF Chimera is a program for the interactive visualization and analysis of molecular structures and related data, including density maps, trajectories, and sequence alignments. It is available free of charge for noncommercial use. Commercial users, please see Chimera commercial licensing.

We encourage Chimera users to try ChimeraX for much better performance with large structures, as well as other major advantages and completely new features. ChimeraX includes a significant subset of Chimera features (with more to come, see the missing features list) and is under active development. Users may choose to use both programs, and it is fine to have both installed.

Chimera is no longer under active development, and is only updated for critical maintenance. Chimera development was supported by a grant from the National Institutes of Health (P41-GM103311) that ended in 2018.

Feature Highlight

Molecular Graphics

• stick, ball-and-stick, CPK, ribbon, pipe-and-plank, and nucleotide display styles
• molecular surfaces
• highly intuitive rotation, translation, and scaling with the mouse
• Side View for adjusting clipping planes and scaling
• interactive color editing in various color spaces (RGB, CMYK, etc.) with transparency
• ability to save high-resolution images for presentation and publication
• stereo (side-by-side and time-sequential)

(More features...)

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Gallery Sample

Peroxiredoxin Wreath

Peroxiredoxins are enzymes that help cells cope with stressors such as high levels of reactive oxygen species. The image shows a decameric peroxiredoxin from human red blood cells (Protein Data Bank entry 1qmv), styled as a holiday wreath.

See also the RBVI holiday card gallery.

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