diff --git a/README.md b/README.md
index 749ec1b..55d055d 100644
--- a/README.md
+++ b/README.md
@@ -32,6 +32,8 @@ Boomer is written in Nim for Linux. Zoomer is ported to C and uses Win32 API.
 | `Q` | Quit app |
 | `0` | Reset zoom |
 | `Mouse button` | Pan |
+| `+` | Zoom in |
+| `-` | Zoom out |
 | `Scroll wheel` | Zoom +/- |
 | `F` | Toggle flashlight |
 | `Ctrl` + `Scroll wheel` | Change size of flashlight |
diff --git a/src/zoomer_main.c b/src/zoomer_main.c
index 3ce18c4..ce816f7 100644
--- a/src/zoomer_main.c
+++ b/src/zoomer_main.c
@@ -188,6 +188,14 @@ void key_callback(GLFWwindow* window, int key, int scancode, int action, int mod
         case GLFW_KEY_ESCAPE:
             quitting = true;
         break;
+        case GLFW_KEY_EQUAL:
+        case GLFW_KEY_KP_ADD:
+            camera.scale *= 1.1f;
+        break;
+        case GLFW_KEY_MINUS:
+        case GLFW_KEY_KP_SUBTRACT:
+            camera.scale *= 0.90909f;
+        break;
         case GLFW_KEY_KP_0:
         case GLFW_KEY_0:
             camera.scale = 1.0f;