diff --git a/ip_range/ip_range.go b/ip_range/ip_range.go
index 51018b4..be35b18 100644
--- a/ip_range/ip_range.go
+++ b/ip_range/ip_range.go
@@ -3,9 +3,13 @@ package iprange
 import (
 	"fmt"
 	"net/netip"
+	"regexp"
+	"strconv"
 	"strings"
 )
 
+var maskPattern = regexp.MustCompile(`\b(?:[0-9]{1,3}\.){3}[0-9]{1,3}\b`)
+
 type IpRange struct {
 	segments []ipSegment
 }
@@ -96,7 +100,15 @@ func createSegment(ip string) (ipSegment, error) {
 		}, nil
 
 	case strings.Contains(ip, "/"):
-		if prefix, err := netip.ParsePrefix(ip); err != nil {
+		sec := strings.Split(ip, "/")
+		ip := sec[0]
+		mask := sec[1]
+
+		if maskPattern.MatchString(mask) {
+			mask = strconv.Itoa(MaskToBits(mask))
+		}
+
+		if prefix, err := netip.ParsePrefix(ip + "/" + mask); err != nil {
 			return nil, err
 		} else {
 			return &prefixSegments{prefix: prefix}, nil
diff --git a/ip_range/ip_range_test.go b/ip_range/ip_range_test.go
index e4e325c..32f0c9b 100644
--- a/ip_range/ip_range_test.go
+++ b/ip_range/ip_range_test.go
@@ -30,6 +30,31 @@ func TestSingleIp(t *testing.T) {
 	assert.False(t, r.Contains("192.168.0.123"))
 }
 
+func TestSinglePrefix(t *testing.T) {
+	r, err := NewRange("192.168.2.100/32")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	assert.False(t, r.Contains("192.168.2.56"))
+	assert.True(t, r.Contains("192.168.2.100"))
+	assert.False(t, r.Contains("192.168.2.130"))
+}
+
+func TestAllIp(t *testing.T) {
+	r, err := NewRange("0.0.0.0/0")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	assert.True(t, r.Contains("192.168.2.100"))
+	assert.True(t, r.Contains("192.3.2.100"))
+	assert.True(t, r.Contains("192.65.2.100"))
+	assert.True(t, r.Contains("172.168.2.100"))
+	assert.True(t, r.Contains("8.8.8.8"))
+	assert.True(t, r.Contains("114.114.114.114"))
+}
+
 func TestPrefix(t *testing.T) {
 	r, err := NewRange("192.168.2.0/24")
 	if err != nil {
@@ -53,6 +78,18 @@ func TestPrefix2(t *testing.T) {
 	assert.False(t, r.Contains("192.168.2.162"))
 }
 
+func TestDotMask(t *testing.T) {
+	r, err := NewRange("192.168.15.0/255.255.248.0")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	assert.True(t, r.Contains("192.168.8.10"))
+	assert.True(t, r.Contains("192.168.14.162"))
+	assert.False(t, r.Contains("192.168.3.162"))
+	assert.False(t, r.Contains("192.168.2.162"))
+}
+
 func TestRange(t *testing.T) {
 	r, err := NewRange("192.168.2.20-192.168.2.30")
 	if err != nil {
diff --git a/ip_range/mask_bits.go b/ip_range/mask_bits.go
new file mode 100644
index 0000000..51e6cc8
--- /dev/null
+++ b/ip_range/mask_bits.go
@@ -0,0 +1,34 @@
+package iprange
+
+import "strings"
+
+var maskBits = map[string]int{
+	"255": 8,
+	"254": 7,
+	"252": 6,
+	"248": 5,
+	"240": 4,
+	"224": 3,
+	"192": 2,
+	"128": 1,
+	"0":   0,
+}
+
+func MaskToBits(mask string) int {
+	bits := 0
+
+	secs := strings.Split(mask, ".")
+	if len(secs) != 4 {
+		panic("the mask is incorrect")
+	}
+
+	for _, s := range secs {
+		if v, ok := maskBits[s]; ok {
+			bits += v
+		} else {
+			panic("the mask is incorrect")
+		}
+	}
+
+	return bits
+}
diff --git a/ip_range/mask_bits_test.go b/ip_range/mask_bits_test.go
new file mode 100644
index 0000000..8fc232b
--- /dev/null
+++ b/ip_range/mask_bits_test.go
@@ -0,0 +1,26 @@
+package iprange
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestMaskToBits(t *testing.T) {
+
+	masks := []struct {
+		mask   string
+		expect int
+	}{
+		{"255.255.255.0", 24},
+		{"255.255.248.0", 21},
+		{"255.255.192.0", 18},
+		{"255.255.255.192", 26},
+	}
+
+	for _, m := range masks {
+		bits := MaskToBits(m.mask)
+		assert.Equal(t, m.expect, bits, fmt.Sprintf("IP:%s 掩码位数错误。", m.mask))
+	}
+}