diff --git a/client/private_msg.go b/client/private_msg.go
index bfd7d922..3f4f07a6 100644
--- a/client/private_msg.go
+++ b/client/private_msg.go
@@ -16,7 +16,7 @@ func (c *QQClient) SendPrivateMessage(target int64, m *message.SendingMessage) *
 	t := time.Now().Unix()
 	imgCount := m.Count(func(e message.IMessageElement) bool { return e.Type() == message.Image })
 	msgLen := message.EstimateLength(m.Elements, 703)
-	if msgLen > 5000 || imgCount > 50 {
+	if msgLen > 703 || imgCount > 50 {
 		return nil
 	}
 	if msgLen > 300 || imgCount > 2 {
diff --git a/message/message.go b/message/message.go
index fba953a7..3920c4fb 100644
--- a/message/message.go
+++ b/message/message.go
@@ -248,7 +248,7 @@ func (msg *SendingMessage) ToFragmented() [][]IMessageElement {
 func EstimateLength(elems []IMessageElement, limit int) int {
 	sum := 0
 	for _, elem := range elems {
-		if sum >= limit {
+		if sum > limit {
 			break
 		}
 		left := int(math.Max(float64(limit-sum), 0))
diff --git a/utils/string.go b/utils/string.go
index ad9803b7..48703a74 100644
--- a/utils/string.go
+++ b/utils/string.go
@@ -55,7 +55,7 @@ func ChineseLength(str string, limit int) int {
 		default:
 			sum += 4
 		}
-		if sum >= limit {
+		if sum > limit {
 			break
 		}
 	}