diff --git a/generator/generator_tests/metadata_parser_test.cpp b/generator/generator_tests/metadata_parser_test.cpp
index fbe11bfe07..8603f192fd 100644
--- a/generator/generator_tests/metadata_parser_test.cpp
+++ b/generator/generator_tests/metadata_parser_test.cpp
@@ -138,49 +138,6 @@ UNIT_TEST(Metadata_ValidateAndFormat_height)
   TEST_EQUAL(md.Get(Metadata::FMD_HEIGHT), "6", ());
 }
 
-UNIT_TEST(Metadata_ValidateAndFormat_building_levels)
-{
-  FeatureParams params;
-  MetadataTagProcessor p(params);
-  Metadata & md = params.GetMetadata();
-
-  p("building:levels", "0");
-  TEST(md.Empty(), ());
-
-  p("building:levels", "0,0000");
-  TEST(md.Empty(), ());
-
-  p("building:levels", "0.0");
-  TEST(md.Empty(), ());
-
-  p("building:levels", "1");
-  TEST_EQUAL(md.Get(Metadata::FMD_BUILDING_LEVELS), "1", ());
-  md.Drop(Metadata::FMD_BUILDING_LEVELS);
-
-  p("building:levels", "3.2");
-  TEST_EQUAL(md.Get(Metadata::FMD_BUILDING_LEVELS), "3.2", ());
-  md.Drop(Metadata::FMD_BUILDING_LEVELS);
-
-  p("building:levels", "1.0");
-  TEST_EQUAL(md.Get(Metadata::FMD_BUILDING_LEVELS), "1", ());
-  md.Drop(Metadata::FMD_BUILDING_LEVELS);
-
-
-  p("building:levels", "1.0");
-  p("height", "4.0");
-  TEST_EQUAL(md.Get(Metadata::FMD_BUILDING_LEVELS), "1", ());
-  md.Drop(Metadata::FMD_BUILDING_LEVELS);
-
-  p("height", "4.0");
-  p("building:levels", "1");
-  TEST_EQUAL(md.Get(Metadata::FMD_BUILDING_LEVELS), "1", ());
-  md.Drop(Metadata::FMD_BUILDING_LEVELS);
-  md.Drop(Metadata::FMD_HEIGHT);
-
-  p("building:levels", "Level 1");
-  TEST(md.Empty(), ());
-}
-
 UNIT_TEST(Metadata_ValidateAndFormat_wikipedia)
 {
   char const * kWikiKey = "wikipedia";
diff --git a/generator/generator_tests/osm2meta_test.cpp b/generator/generator_tests/osm2meta_test.cpp
index 57706624de..af4a7c6a56 100644
--- a/generator/generator_tests/osm2meta_test.cpp
+++ b/generator/generator_tests/osm2meta_test.cpp
@@ -40,3 +40,18 @@ UNIT_TEST(ValidateAndFormat_ele)
   TEST_EQUAL(tagProc.ValidateAndFormat_ele("11'"), "3.35", ());
   TEST_EQUAL(tagProc.ValidateAndFormat_ele("11'4\""), "3.45", ());
 }
+
+UNIT_TEST(ValidateAndFormat_building_levels)
+{
+  FeatureParams params;
+  MetadataTagProcessorImpl tp(params);
+  TEST_EQUAL(tp.ValidateAndFormat_building_levels("４"), "4", ());
+  TEST_EQUAL(tp.ValidateAndFormat_building_levels("４floors"), "4", ());
+  TEST_EQUAL(tp.ValidateAndFormat_building_levels("between 1 and ４"), "", ());
+  TEST_EQUAL(tp.ValidateAndFormat_building_levels("0"), "0", ("OSM has many zero-level buildings."));
+  TEST_EQUAL(tp.ValidateAndFormat_building_levels("0.0"), "0", ());
+  TEST_EQUAL(tp.ValidateAndFormat_building_levels(""), "", ());
+  TEST_EQUAL(tp.ValidateAndFormat_building_levels("Level 1"), "", ());
+  TEST_EQUAL(tp.ValidateAndFormat_building_levels("2.51"), "2.5", ());
+  TEST_EQUAL(tp.ValidateAndFormat_building_levels("250"), "", ("Too many levels."));
+}
diff --git a/generator/osm2meta.cpp b/generator/osm2meta.cpp
index 0f4a0ea73d..7455729b58 100644
--- a/generator/osm2meta.cpp
+++ b/generator/osm2meta.cpp
@@ -9,6 +9,8 @@
 
 #include "std/algorithm.hpp"
 #include "std/cctype.hpp"
+#include "std/cmath.hpp"
+#include "std/cstdlib.hpp"
 #include "std/unordered_set.hpp"
 
 namespace
@@ -158,12 +160,19 @@ string MetadataTagProcessorImpl::ValidateAndFormat_height(string const & v) cons
   return MeasurementUtils::OSMDistanceToMetersString(v, false /*supportZeroAndNegativeValues*/, 1);
 }
 
-string MetadataTagProcessorImpl::ValidateAndFormat_building_levels(string const & v) const
+string MetadataTagProcessorImpl::ValidateAndFormat_building_levels(string v) const
 {
-  double d;
-  if (!strings::to_double(v, d) || d == 0)
-    return {};
-  return strings::to_string_dac(d, 1);
+  // https://en.wikipedia.org/wiki/List_of_tallest_buildings_in_the_world
+  auto constexpr kMaxBuildingLevelsInTheWorld = 167;
+  // Some mappers use full width unicode digits. We can handle that.
+  strings::NormalizeDigits(v);
+  char * stop;
+  char const * s = v.c_str();
+  double const levels = strtod(s, &stop);
+  if (s != stop && isfinite(levels) && levels >= 0 && levels <= kMaxBuildingLevelsInTheWorld)
+    return strings::to_string_dac(levels, 1);
+
+  return {};
 }
 
 string MetadataTagProcessorImpl::ValidateAndFormat_denomination(string const & v) const
diff --git a/generator/osm2meta.hpp b/generator/osm2meta.hpp
index 2e9f0969e7..2a334fe6e0 100644
--- a/generator/osm2meta.hpp
+++ b/generator/osm2meta.hpp
@@ -29,7 +29,7 @@ struct MetadataTagProcessorImpl
   string ValidateAndFormat_flats(string const & v) const;
   string ValidateAndFormat_internet(string v) const;
   string ValidateAndFormat_height(string const & v) const;
-  string ValidateAndFormat_building_levels(string const & v) const;
+  string ValidateAndFormat_building_levels(string v) const;
   string ValidateAndFormat_denomination(string const & v) const;
   string ValidateAndFormat_wikipedia(string v) const;