diff --git a/tests/test_parser.py b/tests/test_parser.py
new file mode 100644
index 0000000..7ea830b
--- /dev/null
+++ b/tests/test_parser.py
@@ -0,0 +1,122 @@
+"""Tests for cron expression parsing and validation."""
+
+import pytest
+from cronparse.parser import validate_cron, parse_cron, parse_field_value
+
+
+class TestValidateCron:
+    """Tests for validate_cron function."""
+
+    def test_valid_every_minute(self):
+        """Test valid every minute expression."""
+        is_valid, error = validate_cron("* * * * *")
+        assert is_valid is True
+        assert error is None
+
+    def test_valid_daily_at_nine_am(self):
+        """Test valid daily at 9 AM expression."""
+        is_valid, error = validate_cron("0 9 * * *")
+        assert is_valid is True
+        assert error is None
+
+    def test_valid_every_five_minutes(self):
+        """Test valid every 5 minutes expression."""
+        is_valid, error = validate_cron("*/5 * * * *")
+        assert is_valid is True
+        assert error is None
+
+    def test_valid_with_command(self):
+        """Test valid expression (without command - croniter doesn't parse commands)."""
+        is_valid, error = validate_cron("0 0 * * *")
+        assert is_valid is True
+        assert error is None
+
+    def test_invalid_expression(self):
+        """Test invalid cron expression."""
+        is_valid, error = validate_cron("invalid expression")
+        assert is_valid is False
+        assert error is not None
+
+    def test_invalid_minute_field(self):
+        """Test invalid minute field."""
+        is_valid, error = validate_cron("60 * * * *")
+        assert is_valid is False
+
+    def test_invalid_hour_field(self):
+        """Test invalid hour field."""
+        is_valid, error = validate_cron("* 25 * * *")
+        assert is_valid is False
+
+
+class TestParseCron:
+    """Tests for parse_cron function."""
+
+    def test_parse_every_minute(self):
+        """Test parsing every minute expression."""
+        is_valid, result = parse_cron("* * * * *")
+        assert is_valid is True
+        assert result["minute"] == "*"
+        assert result["hour"] == "*"
+        assert result["day"] == "*"
+        assert result["month"] == "*"
+        assert result["day_of_week"] == "*"
+
+    def test_parse_daily_at_nine_am(self):
+        """Test parsing daily at 9 AM expression."""
+        is_valid, result = parse_cron("0 9 * * *")
+        assert is_valid is True
+        assert result["minute"] == "0"
+        assert result["hour"] == "9"
+
+    def test_parse_with_step(self):
+        """Test parsing expression with step values."""
+        is_valid, result = parse_cron("*/15 * * * *")
+        assert is_valid is True
+        assert result["minute"] == "*/15"
+
+    def test_parse_with_range(self):
+        """Test parsing expression with range values."""
+        is_valid, result = parse_cron("0 9-17 * * *")
+        assert is_valid is True
+        assert result["hour"] == "9-17"
+
+    def test_parse_with_command(self):
+        """Test parsing expression with command."""
+        is_valid, result = parse_cron("0 0 * * * /usr/bin/backup")
+        assert is_valid is True
+        assert result["command"] == "/usr/bin/backup"
+
+    def test_invalid_expression_returns_false(self):
+        """Test that invalid expression returns False."""
+        is_valid, result = parse_cron("invalid")
+        assert is_valid is False
+        assert "error" in result
+
+
+class TestParseFieldValue:
+    """Tests for parse_field_value function."""
+
+    def test_parse_asterisk(self):
+        """Test parsing asterisk value."""
+        result = parse_field_value("minute", "*")
+        assert result == ["*"]
+
+    def test_parse_single_value(self):
+        """Test parsing single value."""
+        result = parse_field_value("minute", "5")
+        assert result == [5]
+
+    def test_parse_comma_separated(self):
+        """Test parsing comma-separated values."""
+        result = parse_field_value("minute", "5,10,15")
+        assert result == [5, 10, 15]
+
+    def test_parse_range(self):
+        """Test parsing range."""
+        result = parse_field_value("hour", "9-17")
+        assert result == [9, 10, 11, 12, 13, 14, 15, 16, 17]
+
+    def test_parse_step(self):
+        """Test parsing step value."""
+        result = parse_field_value("minute", "*/5")
+        assert result == ["*/step:5"]