diff -r -u a/config.def.h b/config.def.h
--- a/config.def.h	2022-01-07 06:42:18.000000000 -0500
+++ b/config.def.h	2022-01-23 16:03:42.521951418 -0500
@@ -69,6 +69,7 @@
 	{ MODKEY,                       XK_k,      focusstack,     {.i = -1 } },
 	{ MODKEY,                       XK_i,      incnmaster,     {.i = +1 } },
 	{ MODKEY,                       XK_d,      incnmaster,     {.i = -1 } },
+	{ MODKEY,                       XK_o,      resetnmaster,   {0} },
 	{ MODKEY,                       XK_h,      setmfact,       {.f = -0.05} },
 	{ MODKEY,                       XK_l,      setmfact,       {.f = +0.05} },
 	{ MODKEY,                       XK_Return, zoom,           {0} },
diff -r -u a/dwm.c b/dwm.c
--- a/dwm.c	2022-01-23 16:06:01.221948285 -0500
+++ b/dwm.c	2022-01-23 16:05:35.949948855 -0500
@@ -191,6 +191,7 @@
 static void propertynotify(XEvent *e);
 static void quit(const Arg *arg);
 static Monitor *recttomon(int x, int y, int w, int h);
+static void resetnmaster(const Arg *arg);
 static void resize(Client *c, int x, int y, int w, int h, int interact);
 static void resizeclient(Client *c, int x, int y, int w, int h);
 static void resizemouse(const Arg *arg);
@@ -1296,6 +1297,13 @@
 }
 
 void
+resetnmaster(const Arg *arg)
+{
+	selmon->nmaster = selmon->pertag->nmasters[selmon->pertag->curtag] = 1;
+	arrange(selmon);
+}
+
+void
 resize(Client *c, int x, int y, int w, int h, int interact)
 {
 	if (applysizehints(c, &x, &y, &w, &h, interact))