没有内置函数来处理此问题，但可以使用自定义函数，安装第三方加载项或使用替代命令：

使用自定义VBA函数

来源：http://www.freevbcode.com/ShowCode.asp?ID=1512

Public Function URLDecode(StringToDecode As String) As String

Dim TempAns As String
Dim CurChr As Integer

CurChr = 1

Do Until CurChr - 1 = Len(StringToDecode)
  Select Case Mid(StringToDecode, CurChr, 1)
    Case "+"
      TempAns = TempAns & " "
    Case "%"
      TempAns = TempAns & Chr(Val("&h" & _
         Mid(StringToDecode, CurChr + 1, 2)))
       CurChr = CurChr + 2
    Case Else
      TempAns = TempAns & Mid(StringToDecode, CurChr, 1)
  End Select

CurChr = CurChr + 1
Loop

URLDecode = TempAns
End Function

支持第三方插件

来源：SeoTools（需要安装）

=UrlDecode(your_string_here)

使用替换命令

来源：https://searchmarketingcorner.wordpress.com/2013/03/27/creating-an-excel-formula-to-encode-or-unencode-urls/
将下面的公式粘贴到单元格的右侧，以便对该单元格的内容进行URL解码

=SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(CELL_TO_BE_DECODED,"%3F","?"),"%20"," "),"%25", "%"),"%26","&"),"%3D","="),"%7B","{"),"%7D","}"),"%5B","["),"%5D","]")

或者对于GUID，为破折号再添加一个SUBSTITUTE。

=SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(CELL_TO_BE_DECODED,"%3F","?"),"%20"," "),"%25", "%"),"%26","&"),"%3D","="),"%7B","{"),"%7D","}"),"%5B","["),"%5D","]"),"%2D","-")

为了完整起见，这里是URL编码的反向公式。这与URL编码公式相同，但new_text和old_text的位置互换。

=SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(CELL_TO_BE_ENCODED,"?","%3F")," ","%20"),"%","%25"),"&","%26"),"=","%3D"),"{","%7B"),"}","%7D"),"[","%5B"),"]","%5D")

或者对于GUID，为破折号再添加一个SUBSTITUTE。

=SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(CELL_TO_BE_ENCODED,"?","%3F")," ","%20"),"%","%25"),"&","%26"),"=","%3D"),"{","%7B"),"}","%7D"),"[","%5B"),"]","%5D"),"-","%2D")

下面是一个实际工作的用户定义函数（UDF）。
在标准代码模块中，放置以下例程：

Public Function URLDecode(url$) As String
    With CreateObject("ScriptControl")
        .Language = "JavaScript"
        URLDecode = .Eval("unescape(""" & url & """)")
    End With
End Function

现在，您可以从工作表调用它，就像内置的Excel函数一样。
例如，如果编码的URL文本位于单元格A1中，则可以在单元格B1中输入以下公式：

=URLDecode(A1)

就是这样。完全解码的URL现在在单元格B1中。
请注意，这是真实的的交易。这不是试图取代几个字符。这通过Microsoft Script Control使用JavaScript的全部功能来完全解码URL。

下面添加了对URL中逗号的解码。只需要为%2C添加一个SUBSTITUTE。这只是添加到卡洛斯的职位从4年前。

=SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(CELL_TO_BE_DECODED,"%3F","?"),"%20"," "),"%25", "%"),"%26","&"),"%3D","="),"%7B","{"),"%7D","}"),"%5B","["),"%5D","]"),"%2D","-"),"%2C",",")

您可以在没有VBA的情况下使用数组公式来执行此操作。如果A1是要解码的单元格，请输入此公式，然后按Ctrl-Shift-Enter键：

=TEXTJOIN("", FALSE,
    MID(A1,
        FIND("*",
            SUBSTITUTE("%DD"&A1,"%","*",  ROW(INDIRECT("1:"&LEN(A1)-LEN(SUBSTITUTE(A1,"%",""))+1))   )
        ),
        FIND("*",
            SUBSTITUTE(A1&"%","%","*",    ROW(INDIRECT("1:"&LEN(A1)-LEN(SUBSTITUTE(A1,"%",""))+1))   )
        ) - FIND("*",
            SUBSTITUTE("%EE"&A1,"%","*",  ROW(INDIRECT("1:"&LEN(A1)-LEN(SUBSTITUTE(A1,"%",""))+1))   )
        )
    ) & IFERROR(CHAR(HEX2DEC(MID(A1,
        FIND("*",
            SUBSTITUTE(A1&"%","%","*",    ROW(INDIRECT("1:"&LEN(A1)-LEN(SUBSTITUTE(A1,"%",""))+1))   )
        )+1,
       2
    ))),"")
 )

如果你不按Ctrl-Shift-Enter键，它将无法工作。

现在可以使用递归lambda函数来创建简洁的URL解码器函数。
打开名称管理器并将“DECODEURL”定义为：

=LAMBDA(encodedUrl,
  LET(
    length, LEN(encodedUrl),
    head, LEFT(encodedUrl, 1),
    IF(length < 3,
      encodedUrl,
      IF(head = "%",
        CONCAT(
          CHAR(HEX2DEC(MID(encodedUrl, 2, 2))),
          DECODEURL(RIGHT(encodedUrl, length - 3))
        ),
        CONCAT(
          head,
          DECODEURL(RIGHT(encodedUrl, length - 1))
        )
      )
    )
  )
)

然后，您可以简单地使用=DECODEURL(CELL_TO_BE_DECODED)调用该函数。

备注

1.没有输入验证，因此如果URL中存在无效字符串（例如%A%），则此函数将返回#NUM!。
1.确保函数定义中没有制表符，因为这将阻止Excel将其识别为有效公式。