diff --git a/DOCUMENTATION.md b/DOCUMENTATION.md
index cd16dc6b..ea65aaf5 100644
--- a/DOCUMENTATION.md
+++ b/DOCUMENTATION.md
@@ -2349,6 +2349,14 @@ Supported format for `TIMEDELTA`: `[+-]?[0-9]+[WDHM]`
 
 Supported placeholders for `DESCRIPTION` see `conversion_bday_summary_template`
 
+##### conversion_bday_age_max
+
+_(>= 3.7.5)_
+
+Global max limit of "bday" age, only active in case of `{age}` is used as placeholder
+
+Default: `99`
+
 ## Supported Clients
 
 Radicale has been tested with:
diff --git a/config b/config
index 455b481e..19aab2b7 100644
--- a/config
+++ b/config
@@ -366,6 +366,11 @@
 #  Example: "-15H;BDAY tomorrow|9H;BDAY today"
 #conversion_bday_alarm_trigger_template = ""
 
+# Global max limit of "bday" age
+#  Only active in case of {age} is used as placeholder
+#conversion_bday_age_max = 99
+
+
 [web]
 
 # Web interface backend
diff --git a/radicale/config.py b/radicale/config.py
index 00871ccd..413b0dfa 100644
--- a/radicale/config.py
+++ b/radicale/config.py
@@ -606,6 +606,10 @@ DEFAULT_CONFIG_SCHEMA: types.CONFIG_SCHEMA = OrderedDict([
             "value": "",
             "help": "conversion bday alarm trigger template",
             "type": str}),
+        ("conversion_bday_age_max", {
+            "value": 99,
+            "help": "conversion bday age max",
+            "type": positive_int}),
         ])),
     ("hook", OrderedDict([
         ("type", {