diff --git a/lib/screenutil.dart b/lib/screenutil.dart
index cb605cd..ec99a23 100644
--- a/lib/screenutil.dart
+++ b/lib/screenutil.dart
@@ -97,7 +97,7 @@ class ScreenUtil {
   /// Adapted to the device width of the UI Design.
   /// Height can also be adapted according to this to ensure no deformation ,
   /// if you want a square
-  num setWidth(num width) => width * scaleWidth;
+  double setWidth(num width) => width * scaleWidth;
 
   /// 根据UI设计的设备高度适配
   /// 当发现UI设计中的一屏显示的与当前样式效果不符合时,
@@ -107,14 +107,14 @@ class ScreenUtil {
   /// It is recommended to use this method to achieve a high degree of adaptation
   /// when it is found that one screen in the UI design
   /// does not match the current style effect, or if there is a difference in shape.
-  num setHeight(num height) => height * scaleHeight;
+  double setHeight(num height) => height * scaleHeight;
 
   ///字体大小适配方法
-  ///@param [fontSize] UI设计上字体的大小,单位px.
+  ///- [fontSize] UI设计上字体的大小,单位px.
   ///Font size adaptation method
-  ///@param [fontSize] The size of the font on the UI design, in px.
-  ///@param [allowFontScaling]
-  num setSp(num fontSize, {bool allowFontScalingSelf}) =>
+  ///- [fontSize] The size of the font on the UI design, in px.
+  ///- [allowFontScaling]
+  double setSp(num fontSize, {bool allowFontScalingSelf}) =>
       allowFontScalingSelf == null
           ? (allowFontScaling
               ? (fontSize * scaleText)
diff --git a/lib/size_extension.dart b/lib/size_extension.dart
index 2ae5a49..d909ffc 100644
--- a/lib/size_extension.dart
+++ b/lib/size_extension.dart
@@ -2,25 +2,25 @@ import 'package:flutter_screenutil/screenutil.dart';
 
 extension SizeExtension on num {
   ///[ScreenUtil.setWidth]
-  num get w => ScreenUtil().setWidth(this);
+  double get w => ScreenUtil().setWidth(this);
 
   ///[ScreenUtil.setHeight]
-  num get h => ScreenUtil().setHeight(this);
+  double get h => ScreenUtil().setHeight(this);
 
   ///[ScreenUtil.setSp]
-  num get sp => ScreenUtil().setSp(this);
+  double get sp => ScreenUtil().setSp(this);
 
   ///[ScreenUtil.setSp]
-  num get ssp => ScreenUtil().setSp(this, allowFontScalingSelf: true);
+  double get ssp => ScreenUtil().setSp(this, allowFontScalingSelf: true);
 
   ///[ScreenUtil.setSp]
-  num get nsp => ScreenUtil().setSp(this, allowFontScalingSelf: false);
+  double get nsp => ScreenUtil().setSp(this, allowFontScalingSelf: false);
 
   ///屏幕宽度的倍数
   ///Multiple of screen width
-  num get wp => ScreenUtil().screenWidth * this;
+  double get wp => ScreenUtil().screenWidth * this;
 
   ///屏幕高度的倍数
   ///Multiple of screen height
-  num get hp => ScreenUtil().screenHeight * this;
+  double get hp => ScreenUtil().screenHeight * this;
 }