The design is heavily inspired by the Vim text editor, and the authors try to maintain consistency with it wherever possible.

Once activated, Pentadactyl removes all Firefox's default user interface chrome (except for the tab bar) and adds a Vim-inspired command line at the bottom of the window.

[3] After the split Pentadactyl differentiated itself with improved start timing, ability to use the extension without restarting Firefox after installation and some changes for consistency with Vim.

"[1] In June 2011, Chad Perrin of TechRepublic noted: "As a former Vimperator user who has spent substantial time in surf, Uzbl, and Vimium, as well as more cursory time trying out other browsers and Chromium extensions that offer similar interface options, I am much happier with Pentadactyl than any of the alternatives.

Its command functionality, in-application help documentation, completeness, configurability, stability, and (for those using the nightly builds, at least) currency are all superior to the other possibilities for vi-like keybindings in a browser.