diff --git a/bumblebee_status/util/format.py b/bumblebee_status/util/format.py
index 198e995..65242a3 100644
--- a/bumblebee_status/util/format.py
+++ b/bumblebee_status/util/format.py
@@ -68,7 +68,7 @@ def astemperature(val, unit="metric"):
     :return: temperature representation of the input value
     :rtype: string
     """
-    return "{}°{}".format(int(val), __UNITS.get(unit, __UNITS["default"]))
+    return "{}°{}".format(int(val), __UNITS.get(unit.lower(), __UNITS["default"]))
 
 
 def byte(val, fmt="{:.2f}"):
diff --git a/tests/util/test_format.py b/tests/util/test_format.py
index 4dda6e9..1e34dec 100644
--- a/tests/util/test_format.py
+++ b/tests/util/test_format.py
@@ -110,4 +110,7 @@ def test_temperature():
     assert astemperature(-100, "kelvin") == "-100°K"
 
 
+def test_temperature_case():
+    assert astemperature(100, "ImPeRiAl") == "100°F"
+
 # vim: tabstop=8 expandtab shiftwidth=4 softtabstop=4