diff --git a/core/units.h b/core/units.h
index 3a59693b9..4aa3e6962 100644
--- a/core/units.h
+++ b/core/units.h
@@ -247,11 +247,6 @@ static inline long feet_to_mm(double feet)
 	return lrint(feet * 304.8);
 }
 
-static inline int to_feet(depth_t depth)
-{
-	return int_cast<int>(mm_to_feet(depth.mm));
-}
-
 static inline double mkelvin_to_C(int mkelvin)
 {
 	return (mkelvin - ZERO_C_IN_MKELVIN) / 1000.0;
diff --git a/tests/testunitconversion.cpp b/tests/testunitconversion.cpp
index 84ee30a99..3a609714d 100644
--- a/tests/testunitconversion.cpp
+++ b/tests/testunitconversion.cpp
@@ -11,7 +11,6 @@ void TestUnitConversion::testUnitConversions()
 	QCOMPARE(nearly_equal(cuft_to_l(1), 28.316847), true);
 	QCOMPARE(nearly_equal(mm_to_feet(1000), 3.280840), true);
 	QCOMPARE(feet_to_mm(1), 305L);
-	QCOMPARE(to_feet(depth_t{ .mm = 1'000}), 3);
 	QCOMPARE(nearly_equal(mkelvin_to_C(647000), 373.85), true);
 	QCOMPARE(nearly_equal(mkelvin_to_F(647000), 704.93), true);
 	QCOMPARE(F_to_mkelvin(704.93), 647000UL);