diff --git a/src/Magnum/TextureTools/Atlas.cpp b/src/Magnum/TextureTools/Atlas.cpp
index d38c49e40..da0547d86 100644
--- a/src/Magnum/TextureTools/Atlas.cpp
+++ b/src/Magnum/TextureTools/Atlas.cpp
@@ -192,7 +192,7 @@ bool atlasLandfillAddSortedFlipped(Implementation::AtlasLandfillState& state, co
 AtlasLandfill::AtlasLandfill(const Vector3i& size):_state{InPlaceInit} {
     CORRADE_ASSERT(size.x(), "TextureTools::AtlasLandfill: expected non-zero width, got" << Debug::packed << size, );
     CORRADE_ASSERT(size.y() || size.z() == 1, "TextureTools::AtlasLandfill: expected a single array slice for unbounded height, got" << Debug::packed << size, );
-    CORRADE_ASSERT(size.x() <= 65536, "TextureTools::AtlasLandfill: expected width to fit into 16 bits, got" << Debug::packed << size, );
+    CORRADE_ASSERT(size.y() <= 65536, "TextureTools::AtlasLandfill: expected height to fit into 16 bits, got" << Debug::packed << size, );
 
     /* Change y / z = 0 to y / z = MAX so the algorithm doesn't need to branch
        on that internally */
diff --git a/src/Magnum/TextureTools/Test/AtlasTest.cpp b/src/Magnum/TextureTools/Test/AtlasTest.cpp
index bfe6870b6..6ddc62e8c 100644
--- a/src/Magnum/TextureTools/Test/AtlasTest.cpp
+++ b/src/Magnum/TextureTools/Test/AtlasTest.cpp
@@ -979,23 +979,23 @@ void AtlasTest::landfillInvalidSize() {
 
     /* These are fine */
     AtlasLandfill{{16, 0}};
-    AtlasLandfill{{65536, 16}};
+    AtlasLandfill{{16, 65536}};
     AtlasLandfill{{16, 16, 0}};
-    AtlasLandfill{{65536, 16, 16}};
+    AtlasLandfill{{16, 65536, 16}};
 
     std::ostringstream out;
     Error redirectError{&out};
     AtlasLandfill{{0, 16}};
-    AtlasLandfill{{65537, 16}};
+    AtlasLandfill{{16, 65537}};
     AtlasLandfill{{0, 16, 16}};
     AtlasLandfill{{16, 0, 16}};
-    AtlasLandfill{{65537, 16, 16}};
+    AtlasLandfill{{16, 65537, 16}};
     CORRADE_COMPARE_AS(out.str(),
         "TextureTools::AtlasLandfill: expected non-zero width, got {0, 16, 1}\n"
-        "TextureTools::AtlasLandfill: expected width to fit into 16 bits, got {65537, 16, 1}\n"
+        "TextureTools::AtlasLandfill: expected height to fit into 16 bits, got {16, 65537, 1}\n"
         "TextureTools::AtlasLandfill: expected non-zero width, got {0, 16, 16}\n"
         "TextureTools::AtlasLandfill: expected a single array slice for unbounded height, got {16, 0, 16}\n"
-        "TextureTools::AtlasLandfill: expected width to fit into 16 bits, got {65537, 16, 16}\n",
+        "TextureTools::AtlasLandfill: expected height to fit into 16 bits, got {16, 65537, 16}\n",
         TestSuite::Compare::String);
 }