diff --git a/app/src/main/java/org/secuso/privacyfriendlyrulerapp/activities/CalibrationActivity.java b/app/src/main/java/org/secuso/privacyfriendlyrulerapp/activities/CalibrationActivity.java
index e49b4a0..b8b3d73 100644
--- a/app/src/main/java/org/secuso/privacyfriendlyrulerapp/activities/CalibrationActivity.java
+++ b/app/src/main/java/org/secuso/privacyfriendlyrulerapp/activities/CalibrationActivity.java
@@ -50,7 +50,7 @@ public void onClick(View view) {
                     if (inchMode) {
                         length = (float) (length * 25.4);
                     }
-                    length = Math.min(40, Math.max(3, length));
+                    length = Math.min(200, Math.max(3, length));
                     SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(getBaseContext());
                     float dpmm = 300 / length;
                     prefs.edit().putFloat("dpmm", dpmm).commit();