diff --git a/cron_validator/util.py b/cron_validator/util.py
index 559a88b..55ff15c 100644
--- a/cron_validator/util.py
+++ b/cron_validator/util.py
@@ -1,4 +1,5 @@
 import datetime
+import re
 
 import dateutil.parser
 import pytz
@@ -29,3 +30,27 @@ def str_to_datetime(datetime_str, tz_name="UTC"):
     :return:
     """
     return dateutil.parser.parse(datetime_str).replace(tzinfo=get_tz(tz_name))
+
+
+def replace_names(expression):
+    """
+
+    :param expression:
+    :return:
+    """
+    parts = expression.split(" ")
+    month_names = ["jan", "feb", "mar", "apr", "may", "jun", "jul", "aug", "sep", "oct", "nov", "dec"]
+    day_of_week_names = ["sun", "mon", "tue", "wed", "thu", "fri", "sat"]
+    month_names_re = re.compile(rf"(?<![\d\/])({'|'.join(month_names)})(?!\d)", re.IGNORECASE)
+    day_of_week_names_re = re.compile(rf"(?<![\d\/])({'|'.join(day_of_week_names)})(?!\d)", re.IGNORECASE)
+    parts[3] = re.sub(
+        month_names_re, 
+        lambda m: str(month_names.index(m.group().lower()) + 1), 
+        parts[3]
+    )
+    parts[4] = re.sub(
+        day_of_week_names_re, 
+        lambda m: str(day_of_week_names.index(m.group().lower())), 
+        parts[4]
+    )
+    return " ".join(parts)
\ No newline at end of file
diff --git a/cron_validator/validator.py b/cron_validator/validator.py
index 6eeaa13..bfd5cd1 100644
--- a/cron_validator/validator.py
+++ b/cron_validator/validator.py
@@ -1,7 +1,7 @@
 from dateutil import rrule
 
 from .regexes import ElementPart, Version, element_kind_map, regex_dict
-from .util import ts_to_datetime
+from .util import replace_names, ts_to_datetime
 
 
 class CronValidator:
@@ -12,6 +12,7 @@ def parse(cls, expression, version=Version.UNIX):
         :param str expression:
         :return:
         """
+        expression = replace_names(expression)
         parts = expression.split(" ")
         if len(parts) != 5:
             raise ValueError("Invalid expression")
diff --git a/test/test_util.py b/test/test_util.py
index 2bb1dad..7eb5cdf 100644
--- a/test/test_util.py
+++ b/test/test_util.py
@@ -1,6 +1,6 @@
 from dateutil import rrule
 
-from cron_validator.util import str_to_datetime
+from cron_validator.util import replace_names, str_to_datetime
 
 tz_name = "Asia/Ho_Chi_Minh"
 utc_tz = "UTC"
@@ -33,3 +33,12 @@ def test_iterator_day():
     assert delta.total_seconds() < 0
     for dt in rrule.rrule(rrule.MINUTELY, dtstart=dt1, until=dt2):
         print(dt)
+
+
+def test_replace_names():
+    assert replace_names("* * * */2,3 6") == "* * * */2,3 6"
+    assert replace_names("* * * may fri") == "* * * 5 5"
+    assert replace_names("* * * jan-sep,nov mon/2") == "* * * 1-9,11 1/2"
+    assert replace_names("* * * feb,aug,oct tue,WED,sAT") == "* * * 2,8,10 2,3,6"
+    assert replace_names("* * * MAR-apr thu-fri") == "* * * 3-4 4-5"
+    assert replace_names("* * * mAy,jun,JUL-DEC SUN/3") == "* * * 5,6,7-12 0/3"
diff --git a/test/test_valid_regex.py b/test/test_valid_regex.py
index a49e46b..af1f869 100644
--- a/test/test_valid_regex.py
+++ b/test/test_valid_regex.py
@@ -107,3 +107,32 @@ def test_validator_day_of_week_part():
     assert_validate_successfully("* * * * */6")
     assert_validate_fail("* * * * */0")
     assert_validate_fail("* * * * */7")
+
+
+def test_validator_month_names():
+    assert_validate_successfully("* * * jan *")
+    assert_validate_successfully("* * * FEB,mar,Apr *")
+    assert_validate_successfully("* * * MAY-JUL *")
+    assert_validate_successfully("* * * jun-Aug *")
+    assert_validate_successfully("* * * Sep,Oct *")
+    assert_validate_successfully("* * * dec/3 *")
+    assert_validate_fail("* * * January *")
+    assert_validate_fail("* * * jan1 *")
+    assert_validate_fail("* * * 1jan *")
+    assert_validate_fail("* * * 2/feb *")
+    assert_validate_fail("* * * */feb *")
+    assert_validate_fail("* * * NOV/0 *")
+
+
+def test_validator_day_of_week_names():
+    assert_validate_successfully("* * * * sun")
+    assert_validate_successfully("* * * * mon,TUE,Wed")
+    assert_validate_successfully("* * * * FRI-SAT")
+    assert_validate_successfully("* * * * wed/2")
+    assert_validate_fail("* * * * Sunday")
+    assert_validate_fail("* * * * sun,mon-fri")
+    assert_validate_fail("* * * * tue/0")
+    assert_validate_fail("* * * * */mon")
+    assert_validate_fail("* * * * 1/wed")
+    assert_validate_fail("* * * * mon/mon")
+