diff --git a/core/src/main/java/com/alibaba/fastjson2/JSONWriterUTF16.java b/core/src/main/java/com/alibaba/fastjson2/JSONWriterUTF16.java
index 791b9b4ab..9f3592cd5 100644
--- a/core/src/main/java/com/alibaba/fastjson2/JSONWriterUTF16.java
+++ b/core/src/main/java/com/alibaba/fastjson2/JSONWriterUTF16.java
@@ -1430,7 +1430,9 @@ class JSONWriterUTF16
     @Override
     public final void writeName8Raw(long name) {
         int off = this.off;
-        int minCapacity = off + 13 + pretty * level;
+        int minCapacity = off
+                + 13 // 8 + quote 2 + comma 1 + colon 1 + pretty 1
+                + pretty * level;
         char[] chars = this.chars;
         if (minCapacity > chars.length) {
             chars = grow(minCapacity);
diff --git a/core/src/main/java/com/alibaba/fastjson2/JSONWriterUTF8.java b/core/src/main/java/com/alibaba/fastjson2/JSONWriterUTF8.java
index d8f874152..33c6c6d85 100644
--- a/core/src/main/java/com/alibaba/fastjson2/JSONWriterUTF8.java
+++ b/core/src/main/java/com/alibaba/fastjson2/JSONWriterUTF8.java
@@ -1310,9 +1310,11 @@ final class JSONWriterUTF8
     }
 
     @Override
-    public final void writeName8Raw(long name) {
+    public void writeName8Raw(long name) {
         int off = this.off;
-        int minCapacity = off + 13 + pretty * level;
+        int minCapacity = off
+                + 13 // 8 + quote 2 + comma 1 + colon 1 + pretty 1
+                + pretty * level;
         byte[] bytes = this.bytes;
         if (minCapacity > bytes.length) {
             bytes = grow(minCapacity);