diff --git a/silkaj/constants.py b/silkaj/constants.py
index f941a370a8d9b361e2fc0e999778043de7a882c7..48e713ce649aba538203d3f2d79da8c3d87cd09c 100644
--- a/silkaj/constants.py
+++ b/silkaj/constants.py
@@ -32,3 +32,10 @@ MINIMAL_ABSOLUTE_TX_AMOUNT = 0.01
 MINIMAL_RELATIVE_TX_AMOUNT = 1e-6
 CENT_MULT_TO_UNIT = 100
 SHORT_PUBKEY_SIZE = 8
+
+# pendulum constants
+DATE = "LL"
+HOUR = "LTS"
+ALL = "LLL"
+# Not ISO 8601 compliant but common
+ALL_DIGITAL = "YYYY-MM-DD HH:mm:ss"