Please Note: This article is written for users of the following Microsoft Word versions: 2007, 2010, 2013, 2016, 2019, 2021, 2024, and Word in Microsoft 365. If you are using an earlier version (Word 2003 or earlier), this tip may not work for you. For a version of this tip written specifically for earlier versions of Word, click here: Determining the Length of a Non-Document Text File.
Written by Allen Wyatt (last updated June 7, 2025)
This tip applies to Word 2007, 2010, 2013, 2016, 2019, 2021, 2024, and Word in Microsoft 365
Several other WordTips have discussed opening, reading, writing, appending, and closing text files in your macros. Another command associated with sequential text files is the LOF function. If used on an open file, it returns the length of the file, in bytes. In other words, you can determine the number of characters in the file. This can come in handy if you are processing a text file character by character. You can determine the length of the file and then read that many characters before you finish processing the file.
The following code fragment is an example of how the LOF function is used:
Open "MyFile.Dat" for Input as #1 FileLen = LOF(1)
After the code is executed, the value in the FileLen variable will be the number of bytes in the MyFile.Dat file.
Note, again, that the file must be open to use the LOF function. (That's the purpose of the first line in the code fragment—to open the file.) If you don't want to open the file, then you can use the FileLen function to determine a file's length. This requires just a single code line:
Please Note:
This article is written for users of the following Microsoft Word versions: 2007, 2010, 2013, 2016, 2019, 2021, 2024, and Word in Microsoft 365. If you are using an earlier version (Word 2003 or earlier), this tip may not work for you. For a version of this tip written specifically for earlier versions of Word, click here:
FileLen = FileLen("MyFile.Dat")
Note that you enclose the filename in quote marks or use a string variable to contain the filename. You can also include a path in the filename parameter. If the file doesn't exist, then FileLen returns an error.
Note:
WordTips is your source for cost-effective Microsoft Word training. (Microsoft Word is the most popular word processing software in the world.) This tip (11111) applies to Microsoft Word 2007, 2010, 2013, 2016, 2019, 2021, 2024, and Word in Microsoft 365. You can find a version of this tip for the older menu interface of Word here: Determining the Length of a Non-Document Text File.
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