diff --git a/game/src/ui/uiman.c b/game/src/ui/uiman.c
index ee16d0c..ae163aa 100644
--- a/game/src/ui/uiman.c
+++ b/game/src/ui/uiman.c
@@ -24,12 +24,15 @@ uiman_init ()
   Widget_label_printf (game_name, "%s %s", GAME_NAME, GAME_VERSION);
   
   Widget *frame_time = Widget_label_new (NULL, TEXT_ALIGN_LEFT);
-  Widget_set_on_tick (frame_time, uicb_label_show_float, &delta_time);
+  Widget_set_on_tick (frame_time, uicb_label_show_float,
+		      CallbackFormatData_new_float ("Frame: %.2f s", &delta_time));
   
   Widget *entities_rendered = Widget_label_new (NULL, TEXT_ALIGN_LEFT);
   Widget *chunks_rendered = Widget_label_new (NULL, TEXT_ALIGN_LEFT);
-  Widget_set_on_tick (entities_rendered, uicb_label_show_int, &n_frame_ents);
-  Widget_set_on_tick (chunks_rendered, uicb_label_show_int, &n_frame_chunks);
+  Widget_set_on_tick (entities_rendered, uicb_label_show_int,
+		      CallbackFormatData_new_int ("Entities: %d", &n_frame_ents));
+  Widget_set_on_tick (chunks_rendered, uicb_label_show_int,
+		      CallbackFormatData_new_int ("Chunks: %d", &n_frame_chunks));
 
   Widget *container2 = Widget_container_new (true);
   Widget_add_child (container2, entities_rendered);
@@ -39,11 +42,14 @@ uiman_init ()
   Widget *pos_y = Widget_label_new (NULL, TEXT_ALIGN_RIGHT);
   Widget *pos_z = Widget_label_new (NULL, TEXT_ALIGN_RIGHT);
   Widget_label_set_text_color (pos_x, 1.0, 0.0, 0.0, 1.0);
-  Widget_set_on_tick (pos_x, uicb_label_show_float, &camera_position[0]);
+  Widget_set_on_tick (pos_x, uicb_label_show_float,
+		      CallbackFormatData_new_float ("X: %.2f", &camera_position[0]));
   Widget_label_set_text_color (pos_y, 0.0, 1.0, 0.0, 1.0);
-  Widget_set_on_tick (pos_y, uicb_label_show_float, &camera_position[1]);
+  Widget_set_on_tick (pos_y, uicb_label_show_float,
+		      CallbackFormatData_new_float ("Y: %.2f", &camera_position[1]));
   Widget_label_set_text_color (pos_z, 0.0, 1.0, 1.0, 1.0);
-  Widget_set_on_tick (pos_z, uicb_label_show_float, &camera_position[2]);
+  Widget_set_on_tick (pos_z, uicb_label_show_float,
+		      CallbackFormatData_new_float ("Z: %.2f", &camera_position[2]));
   
   Widget *container3 = Widget_container_new (true);
   Widget_add_child (container3, pos_x);
@@ -64,7 +70,6 @@ uiman_init ()
   Widget_add_child (container4, wireframe_button);
   Widget_add_child (container4, flight_button);
 
-  
   Widget_add_child (container, game_name);
   Widget_add_child (container, frame_time);
   Widget_add_child (container, container2);
diff --git a/game/src/ui/widget.c b/game/src/ui/widget.c
index b9665d2..ad1ccd5 100644
--- a/game/src/ui/widget.c
+++ b/game/src/ui/widget.c
@@ -3,7 +3,6 @@
 /* TODO: Layout container children scaling, so some children can be
    smaller, some bigger, etc. Perhaps android-esque LinearLayout
    weight? */
-/* TODO: Label callback with format. */
 /* TODO: Widget borders. */
 
 static SimpleMesh quad;
@@ -335,18 +334,36 @@ Widget_label_set_text_color (Widget *widget, float r, float g, float b, float a)
   glm_vec4_copy ((vec4) { r, g, b, a }, widget->label.text_color);
 }
 
+CallbackFormatData *
+CallbackFormatData_new_int (const char *format, int *value)
+{
+  CallbackFormatData *data = g_new (CallbackFormatData, 1);
+  data->format = format;
+  data->int_value = value;
+  return data;
+}
+
+CallbackFormatData *
+CallbackFormatData_new_float (const char *format, float *value)
+{
+  CallbackFormatData *data = g_new (CallbackFormatData, 1);
+  data->format = format;
+  data->float_value = value;
+  return data;  
+}
+
 void
 uicb_label_show_int (Widget *widget, void *userdata)
 {
-  int *value = userdata;
-  Widget_label_printf (widget, "%d", *value);
+  CallbackFormatData *value = userdata;
+  Widget_label_printf (widget, value->format, *value->int_value);
 }
 
 void
 uicb_label_show_float (Widget *widget, void *userdata)
 {
-  float *value = userdata;
-  Widget_label_printf (widget, "%3.2f", *value);
+  CallbackFormatData *value = userdata;
+  Widget_label_printf (widget, value->format, *value->float_value);
 }
 
 void
diff --git a/game/src/ui/widget.h b/game/src/ui/widget.h
index 89bd576..0002972 100644
--- a/game/src/ui/widget.h
+++ b/game/src/ui/widget.h
@@ -70,6 +70,14 @@ typedef struct Widget
   void *tick_data;
 } Widget;
 
+typedef struct CallbackFormatData {
+  const char *format;
+  union {
+    int *int_value;
+    float *float_value;
+  };
+} CallbackFormatData;
+
 static inline float
 wdg_real_width (mat3 model)
 {
@@ -107,6 +115,9 @@ void Widget_label_set_text (Widget *widget, const char *text);
 void Widget_label_printf (Widget *widget, const char *format, ...);
 void Widget_label_set_text_color (Widget *widget, float r, float g, float b, float a);
 
+CallbackFormatData *CallbackFormatData_new_int (const char *format, int *value);
+CallbackFormatData *CallbackFormatData_new_float (const char *format, float *value);
+
 void uicb_label_show_int (Widget *widget, void *userdata);
 void uicb_label_show_float (Widget *widget, void *userdata);