1 files changed, 3 insertions, 0 deletions
diff --git a/synapse/api/constants.py b/synapse/api/constants.py
index 0860b75905..8547a63535 100644
--- a/synapse/api/constants.py
+++ b/synapse/api/constants.py
@@ -20,6 +20,9 @@
 # the "depth" field on events is limited to 2**63 - 1
 MAX_DEPTH = 2**63 - 1
 
+# the maximum length for a room alias is 255 characters
+MAX_ALIAS_LENGTH = 255
+
 
 class Membership(object):