diff --git a/README.md b/README.md
index 454f59b..0b38dae 100644
--- a/README.md
+++ b/README.md
@@ -24,6 +24,7 @@ require('command-completion').setup {
                   -- see `:help nvim_open_win()` for available options (e.g. 'single', 'double', etc.)
     max_col_num = 5, -- Maximum number of columns to display in the completion window
     min_col_width = 20, -- Minimum width of completion window columns
+    window_width = vim.o.columns, -- Width of the window (defaults to full width)
     use_matchfuzzy = true, -- Whether or not to use `matchfuzzy()` (see `:help matchfuzzy()`) 
                            -- to order completion results
     highlight_selection = true, -- Whether or not to highlight the currently
diff --git a/lua/command-completion.lua b/lua/command-completion.lua
index 2487b48..854fa21 100644
--- a/lua/command-completion.lua
+++ b/lua/command-completion.lua
@@ -22,6 +22,7 @@ local user_opts = {
   border = nil,
   max_col_num = 5,
   min_col_width = 20,
+  window_width = vim.o.columns,
   use_matchfuzzy = true,
   highlight_selection = true,
   highlight_directories = true,
@@ -40,7 +41,7 @@ local directory_hl_nsid = n.create_namespace('__ccs_hls_namespace_directory___')
 local function calc_col_width()
   local col_width
   for i = 1, user_opts.max_col_num do
-    local test_width = math.floor(vim.o.columns / i)
+    local test_width = math.floor(user_opts.window_width / i)
     if test_width <= user_opts.min_col_width then
       return col_width
     else
@@ -60,7 +61,7 @@ local function open_and_setup_win(height)
     relative = 'editor',
     border = user_opts.border,
     style = 'minimal',
-    width = vim.o.columns,
+    width = user_opts.window_width,
     height = height,
     row = vim.o.lines - 2,
     col = 0,