diff --git a/.gitignore b/.gitignore
index 4e7d8d8..7530e6e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,5 +1,19 @@
-venv/
-
+# IDEs
+.vscode/
 .idea/
 
+# Intermediate Coverage file
+.coverage
+
+# Output files
+*.png
+
+# Python runtime
+*.pyc
+*.egg-info
+.pytest_cache
 __pycache__/
+
+# Virtual environments
+venv/
+.venv/
diff --git a/README.md b/README.md
index ad7043c..151f6ae 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,4 @@
-# Oxford RSE Unit Conversion
+# Oxford RSE Unit Conversion - Kirsty McCready
 
 [![Unittest](https://github.com/OxfordRSE/oxrse_unit_conv/actions/workflows/unittest.yml/badge.svg)](https://github.com/OxfordRSE/oxrse_unit_conv/actions/workflows/unittest.yml)
 
diff --git a/src/oxrse_unit_conv/units.py b/src/oxrse_unit_conv/units.py
index ad09e02..3f2657f 100644
--- a/src/oxrse_unit_conv/units.py
+++ b/src/oxrse_unit_conv/units.py
@@ -8,6 +8,9 @@
 hour = Unit(name='hour', abbr='h', si=second, to_si_fun=lambda n: n * 3600)
 h = hour
 
+day = Unit(name='day', abbr='d', si=second, to_si_fun=lambda n: n * 86_400)
+d = day
+
 # meter
 kilometer = Unit(name='kilometer', abbr="km", si=meter, to_si_fun=lambda n: n * 1000)
 km = kilometer
diff --git a/src/tests/test_conversion_core.py b/src/tests/test_conversion_core.py
index 70acff2..178f5e8 100644
--- a/src/tests/test_conversion_core.py
+++ b/src/tests/test_conversion_core.py
@@ -1,6 +1,6 @@
 import unittest
 from oxrse_unit_conv.meta import classes
-from oxrse_unit_conv.units import kilometer, m, m2, m3, s, hour
+from oxrse_unit_conv.units import kilometer, m, m2, m3, s, hour, day
 
 
 class TestConversionCore(unittest.TestCase):
diff --git a/src/tests/test_unit_d.py b/src/tests/test_unit_d.py
new file mode 100644
index 0000000..734fd41
--- /dev/null
+++ b/src/tests/test_unit_d.py
@@ -0,0 +1,13 @@
+import unittest
+from oxrse_unit_conv.units import d, s
+
+class TestDay(unittest.TestCase):
+    def test_SI(self):
+        self.assertTrue(d.si_unit.matches(s))
+
+    def test_basic_conversion(self):
+        self.assertEqual(d.to_si(1), 86_400)
+        self.assertEqual(d.to_unit(10, d), 10)
+
+if __name__ == '__main__':
+    unittest.main()
\ No newline at end of file