diff --git a/lua/symbols-outline/config.lua b/lua/symbols-outline/config.lua
index 2e6a2f0..95ccde6 100644
--- a/lua/symbols-outline/config.lua
+++ b/lua/symbols-outline/config.lua
@@ -72,7 +72,7 @@ end
 
 function M.get_window_width()
   if M.options.relative_width then
-    return math.ceil(vim.api.nvim_win_get_width(0) * (M.options.width / 100))
+    return math.ceil(vim.o.columns * (M.options.width / 100))
   else
     return M.options.width
   end