ViewVC (formerly ViewCVS) is an open-source tool for viewing the contents of CVS and SVN repositories using a web browser.

It is written in Python and the view parameters can be modified directly in a URL using a REST style interface.

ViewVC was inspired by the CVSweb application, an older web-based CVS repository viewer written in Perl.

The original ViewCVS was a Python port of this application, with the intention to add enhancements to the existing functionality.

The eventual maturity of this support meant that the name "ViewCVS" was no longer appropriate, which, combined with SourceForge's lack of support for Subversion at the time, led to the project being renamed "ViewVC" and moving to tigris.org.