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 in addition to nearly all the capabilities of Chimera (details...).

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

Feature Highlight

Multiple Sequence Alignment

Multiple sequence alignment of structure chains in Chimera or realignment of the sequences in an existing alignment can be performed using web services hosted by the UCSF RBVI. The following programs are provided:

• Clustal Omega
• MUSCLE

The result is automatically shown in Multalign Viewer. (Sequences can also be added to an alignment one by one without a web service, but true multiple sequence alignment is often advantageous.) (More features...)

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Gallery Sample

Loop Interactions

The image shows interactions of the delta-1 loop with the rest of hepatitis C virus RNA-dependent RNA polymerase (Protein Data Bank entry 1quv). Loop residues in contact with the rest of the structure (van der Waals overlap ≥ 0.01 Å) are displayed as sticks; interacting surface atoms are shown as red patches. (More samples...)