diff --git a/src/kaleidoscope/Hardware.h b/src/kaleidoscope/Hardware.h
index 0f275f0d..00d45cb0 100644
--- a/src/kaleidoscope/Hardware.h
+++ b/src/kaleidoscope/Hardware.h
@@ -21,6 +21,8 @@
 
 #pragma once
 
+#include "kaleidoscope/MatrixAddr.h"
+
 #ifndef CRGB
 #error cRGB and CRGB *must* be defined before including this header!
 #endif
diff --git a/src/kaleidoscope/hardware/ez/ErgoDox.h b/src/kaleidoscope/hardware/ez/ErgoDox.h
index 1b148406..b534a8c2 100644
--- a/src/kaleidoscope/hardware/ez/ErgoDox.h
+++ b/src/kaleidoscope/hardware/ez/ErgoDox.h
@@ -56,6 +56,11 @@ class ErgoDox : public kaleidoscope::Hardware {
   static constexpr byte matrix_rows = 14;
   static constexpr int8_t led_count = 0;
 
+  typedef MatrixAddr<matrix_rows, matrix_columns> KeyAddr;
+  static constexpr int8_t numKeys() {
+    return matrix_columns * matrix_rows;
+  }
+
   void scanMatrix(void);
   void readMatrix(void);
   void actOnMatrixScan(void);
diff --git a/src/kaleidoscope/hardware/kbdfans/KBD4x.h b/src/kaleidoscope/hardware/kbdfans/KBD4x.h
index dd9d898f..b1c4a13c 100644
--- a/src/kaleidoscope/hardware/kbdfans/KBD4x.h
+++ b/src/kaleidoscope/hardware/kbdfans/KBD4x.h
@@ -45,6 +45,11 @@ class KBD4x: public kaleidoscope::hardware::ATMegaKeyboard {
 
   static constexpr int8_t led_count = 0;
 
+  typedef MatrixAddr<matrix_rows, matrix_columns> KeyAddr;
+  static constexpr int8_t numKeys() {
+    return matrix_columns * matrix_rows;
+  }
+
   void resetDevice();
 };
 
diff --git a/src/kaleidoscope/hardware/keyboardio/Model01.h b/src/kaleidoscope/hardware/keyboardio/Model01.h
index 17cfe499..cc089b65 100644
--- a/src/kaleidoscope/hardware/keyboardio/Model01.h
+++ b/src/kaleidoscope/hardware/keyboardio/Model01.h
@@ -43,6 +43,11 @@ class Model01 : public kaleidoscope::Hardware {
   static constexpr byte matrix_columns = 16;
   static constexpr int8_t led_count = 64;
 
+  typedef MatrixAddr<matrix_rows, matrix_columns> KeyAddr;
+  static constexpr int8_t numKeys() {
+    return matrix_columns * matrix_rows;
+  }
+
   void syncLeds(void);
   void setCrgbAt(byte row, byte col, cRGB color);
   void setCrgbAt(int8_t i, cRGB crgb);
diff --git a/src/kaleidoscope/hardware/olkb/Planck.h b/src/kaleidoscope/hardware/olkb/Planck.h
index d1d38d72..47540244 100644
--- a/src/kaleidoscope/hardware/olkb/Planck.h
+++ b/src/kaleidoscope/hardware/olkb/Planck.h
@@ -41,6 +41,11 @@ class Planck: public kaleidoscope::hardware::ATMegaKeyboard {
   );
 
   static constexpr int8_t led_count = 0;
+
+  typedef MatrixAddr<matrix_rows, matrix_columns> KeyAddr;
+  static constexpr int8_t numKeys() {
+    return matrix_columns * matrix_rows;
+  }
 };
 
 #define PER_KEY_DATA(dflt,                                                       \
diff --git a/src/kaleidoscope/hardware/softhruf/Splitography.h b/src/kaleidoscope/hardware/softhruf/Splitography.h
index 3eb313c9..1078a8a3 100644
--- a/src/kaleidoscope/hardware/softhruf/Splitography.h
+++ b/src/kaleidoscope/hardware/softhruf/Splitography.h
@@ -50,6 +50,11 @@ class Splitography: public kaleidoscope::hardware::ATMegaKeyboard {
   );
 
   static constexpr int8_t led_count = 0;
+
+  typedef MatrixAddr<matrix_rows, matrix_columns> KeyAddr;
+  static constexpr int8_t numKeys() {
+    return matrix_columns * matrix_rows;
+  }
 };
 
 #define PER_KEY_DATA(dflt,                                                       \
diff --git a/src/kaleidoscope/hardware/technomancy/Atreus.h b/src/kaleidoscope/hardware/technomancy/Atreus.h
index 8ecd21c7..4e5fb477 100644
--- a/src/kaleidoscope/hardware/technomancy/Atreus.h
+++ b/src/kaleidoscope/hardware/technomancy/Atreus.h
@@ -65,6 +65,11 @@ class Atreus: public kaleidoscope::hardware::ATMegaKeyboard {
 
   static constexpr int8_t led_count = 0;
 
+  typedef MatrixAddr<matrix_rows, matrix_columns> KeyAddr;
+  static constexpr int8_t numKeys() {
+    return matrix_columns * matrix_rows;
+  }
+
   void resetDevice();
 
  protected:
diff --git a/src/kaleidoscope/hardware/technomancy/Atreus2.h b/src/kaleidoscope/hardware/technomancy/Atreus2.h
index 524bef82..170a7d61 100644
--- a/src/kaleidoscope/hardware/technomancy/Atreus2.h
+++ b/src/kaleidoscope/hardware/technomancy/Atreus2.h
@@ -43,6 +43,11 @@ class Atreus2: public kaleidoscope::hardware::ATMegaKeyboard {
   )
   static constexpr int8_t led_count = 0;
 
+  typedef MatrixAddr<matrix_rows, matrix_columns> KeyAddr;
+  static constexpr int8_t numKeys() {
+    return matrix_columns * matrix_rows;
+  }
+
   void resetDevice();
 
  protected: