diff --git a/test/service/timezone_detector_test.exs b/test/service/timezone_detector_test.exs
new file mode 100644
index 000000000..582aaf814
--- /dev/null
+++ b/test/service/timezone_detector_test.exs
@@ -0,0 +1,65 @@
+defmodule Mobilizon.Service.TimezoneDetectorTest do
+  @moduledoc """
+  Test the timezone detector
+  """
+
+  alias Mobilizon.Service.TimezoneDetector
+
+  use Mobilizon.DataCase
+
+  describe "detect when no geographic data is provided" do
+    test "with timezone" do
+      assert "Europe/Paris" == TimezoneDetector.detect("Europe/Paris", "Europe/Paris")
+    end
+
+    test "with invalid timezone" do
+      assert "Europe/Paris" == TimezoneDetector.detect("Europe/Neuilly", "Europe/Paris")
+    end
+
+    test "with default" do
+      assert "Europe/Paris" == TimezoneDetector.detect(nil, "Europe/Paris")
+    end
+  end
+
+  describe "with geographic data provided" do
+    test "when valid with value" do
+      assert "Europe/Berlin" ==
+               TimezoneDetector.detect(
+                 "Europe/Berlin",
+                 %Geo.Point{coordinates: {4.842569, 45.751718}, properties: %{}, srid: 4326},
+                 "Europe/Moscow"
+               )
+    end
+
+    test "when valid with no value" do
+      assert "Europe/Paris" ==
+               TimezoneDetector.detect(
+                 nil,
+                 %Geo.Point{coordinates: {4.842569, 45.751718}, properties: %{}, srid: 4326},
+                 "Europe/Moscow"
+               )
+    end
+
+    test "when valid with inalid value" do
+      assert "Europe/Paris" ==
+               TimezoneDetector.detect(
+                 "Europe/Neuilly",
+                 %Geo.Point{coordinates: {4.842569, 45.751718}, properties: %{}, srid: 4326},
+                 "Europe/Moscow"
+               )
+    end
+
+    test "with invalid coordinates" do
+      assert "Europe/Moscow" ==
+               TimezoneDetector.detect(
+                 nil,
+                 %Geo.Point{coordinates: {0, 0}, properties: %{}, srid: 4326},
+                 "Europe/Moscow"
+               )
+    end
+
+    test "with no data" do
+      assert "Europe/Paris" == TimezoneDetector.detect("Europe/Neuilly", nil, "Europe/Paris")
+    end
+  end
+end
diff --git a/test/service/workers/export_cleaner_worker.ex b/test/service/workers/export_cleaner_worker.exs
similarity index 100%
rename from test/service/workers/export_cleaner_worker.ex
rename to test/service/workers/export_cleaner_worker.exs