diff --git a/nafuma/xanes/unit_tables.py b/nafuma/xanes/unit_tables.py
new file mode 100644
index 0000000..52ca61c
--- /dev/null
+++ b/nafuma/xanes/unit_tables.py
@@ -0,0 +1,11 @@
+import pandas as pd
+
+def time():
+    # Define matrix for unit conversion for time
+    time = {'h': [1, 60, 3600, 3600000], 'min': [1/60, 1, 60, 60000], 's': [1/3600, 1/60, 1, 1000], 'ms': [1/3600000, 1/60000, 1/1000, 1]}
+    time = pd.DataFrame(time)
+    time.index = ['h', 'min', 's', 'ms']
+
+    return time
+
+