How to Open Password Protected Excel File (2021 Updates)

Kawhi Dumingz
8 min readAug 11, 2021

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Excel, or MS Office, has become an essential part of our everyday life. Whether you are a beginner in Excel, or you are a power user, you need to handle an Excel file one way or the other. From bank account statements to important financial records, Excel is our go-to solution.

Since most of these Excel files contain sensitive information, Microsoft has introduced various methods to protect those content from prying eyes.

This might lead to a serious issue. That is forgetting the password you set previously. In this article, we will cover five different approaches to open password protected Excel file without knowing the password.

Office Encryption Algorithm History

Since it is inception in 1988, MS Office security has come a long way. During the initial phase of Office, they had a simple XOR encryption that could have been cracked very simply. It continued with Office 97, which was purposefully given a weak encryption because of export restrictions in US. It had a rudimentary 40-bit RC4 encryption with MD5 hash. Same thing continued with Office 2000, Office XP, and Office 2003.

Things started to change since Office 2007. Microsoft introduced the 128-bit AES encryption instead of the usual 40-bit one along with new file formats. Office 2010 became twice as secure as Office 2007 with twice the number of hash iterations than Office 2007. Office 2007 had 50,000 hash iterations, whereas Office 2010 had 100,000 hash iterations.

Then with Office 2013, Microsoft changed the encryption algorithm to AES-256 along with SHA-512 hash algorithm. This resulted in stringent security, and thus, required different complex methods to recover/remove those passwords.

In short, he newer the Excel version, the more difficult it is to crack the password.

Excel Password Types

Currently Excel has 4 different types of passwords:

Open Password: The user has to input the correct password before opening the password protected Excel file.

Modify Password: Restrict the user to make certain changes to the worksheets. Only the granted password is provided, the user has the privilege to modify the worksheet.

Read-only Password: Allow Excel spreadsheet to be viewed but cannot be edited or modified in any way.

Workbook Structure Password: Protect the structure of the Excel workbook. By doing this, sheets can not be deleted, moved or renamed.

If you have a password protected Excel file that you want to open but don’t know the password is, please read on. We will list several ways to help you open a password protected Excel file without password. Based on the current situation, you can choose a particular method and apply it.

1. Try Sample or Frequently Used Passwords

The simplest way to open password protected Excel file is, yes, with the password. But if you have forgotten the password or it is a password protected file not owned by you, the first trick is to try sample or frequently used passwords as many as you can. There is no risky for guesting the password. The excel file won’t be locked even after many failed attempts. This is a really good news.

Here is a few sample password you can try out one by one:

You may get some good luck if you are using one of the above passwords. However, if you could not open password protected Excel file in this way, please go through the other methods shared in this post.

2. Rename .xls or .xlsx to .zip (For Old Excel Version)

Technically speaking, Excel is a variant of zip file that follows the Open Office Document standard, which is composed by different worksheets and a configurable xml file. The encryption key is saved in this XML file. We can edit the content to remove password protection from Excel. After that, the protected Excel file no longer needs a password to view.

Unfortunately, this trick only works for old Excel files before Office 2010. This is a complete free and simple methods so you can try it out without any loss. If it did not work, then move on to the next method.

First, change file extension of Excel file from .xls to .zip.

Once the Excel file is converted into a ZIP file, unzip the archive and look for a folder name “xl” without the quotes of course. Inside the folder you would find a file named workbook.xml.

Open workbook.xml file with Notepad app and search for the text “sheetProtection” without the quotes. Now, remove all content marked with red line in the following screenshot, starting from “<sheetProtection”.

Rename the zip file to xls extension at the same location, this will overwrite the original file. This is a safe process and won’t change any of the data in that file.

Now, you can open this Excel and it will not ask you for password.

3. Open Password Protected Excel via PassCue for Excel

PassCue is a well-known software development company that offers various password cracking solutions. PassCue for Excel is a dedicated app for cracking Excel open password and removing Excel Modify password. It is one of the easiest tools to open password protected Excel files.

PassCue for Excel offers three powerful modules to recover forgotten password from Excel file, Brute-force, Dictionary and Mask. It boasts of zero data loss. What’s more, there’s a free version you can test it out. More importantly, they have a timely help desk available and this is great for further customer assistance.

The first step is to download and install PassCue Excel Password Recovery tool from the following link:

https://www.passcue.com/downloads/passcue_for_excel.exe

Launch the program from desktop and you’ll see the below window. For cracking Excel Open password, please click the first option (Recover Open Password from Excel) to proceed.

passcue excel password recovery

Next, press the “Add File” icon to add the password protected Excel file into the program.

After that, you need to select a password recovery type listed on screen. Each attack type has their own pluses and minuses. For example, if you could still remember part of the original password, you can try the Brute-force with Mask attack, and fill out more details with Settings button at the right side. This would do a greta help for recovering the password in much less time.

After settings, press Start button to start password recovery task. You will see the password speed, time duration and current password for checking.

When this process is finished successfully, PassCue for Excel will display the recovered password in a pop-up window. Now, copy the recovered password.

Finally, locate the locked Excel file and open this password protected Excel file with the copied password.

4. Open Password Protected Excel with Online Tool

Password-online.com is a paid online service that decrypts password for a variety of files including Excel, PDF, Word, PowerPoint, 7zip etc. They charge 10 Euros for every successful decryption. However, you have to upload the password protected Excel file to their servers. This may be an issue in case the Excel file does contain sensitive information and cannot be shared with others. Also, if your Excel file is more than 500 MB in size, you need to split the file and then upload it.

Visit their website (https://password-online.com/) and use the Upload your encrypted file button to upload Excel file to its server.

Once the upload is successful, it will ask you to input an email address for receiving notifications.

Now, click the activation link in Email inbox and it starts decrypting the password.

If successful, it asks you to make payments and download the unlocked Excel file.

5. Open Password Protected Excel File with Free Hashcat Software

Hashcat is a quite popular tool among hackers and system analysts. It is a text-based password recovery tool being used to crack various types of passwords ranging from WiFi, Windows, Excel and MS Office products, to PDFs, ZIP files etc.

Although it is a totally free open-source tool, it is mainly for advanced users that knows how to deal with commands. If you feel scared typing a complex text with parameters on a black screen, then this utility is probably not for you.

First, install the program called Office2John from this GitHub repository .

The installation instruction is given in the repository itself.

Now, copy the password protected Excel file to the same folder where Office2John was installed.

Next, download Hashcat utility from its website and decompress the zip file.

At this stage, extract the hash password (not the original password) from the password protected Excel file using the below command:

python office2john.py my.xlsx > hash-password.txt

Remember to replace my.xlsx with the name of your Excel file in the previous step.

Click this link to get the unique hash mode that is related to the version of Excel file:

Once you find the hash mode (25300 for Excel 2016 as example), please type this command to retrieve forgotten password from Excel file:

hashcat -a 0 -m 25300 -o unlocked.txt hash-password.txt /usr/share/wordlists/nmap.lst

Remember to replace 25300 with the hash mode of target Excel version.

Finally, Hashcat will unlock and store the password in the file named unlocked.txt file.

Wrapping Up

Well, opening a password protect Excel has never been easy nowadays! We have so many options available. It could be a desktop software or online password recovery service. It is your turn to choose what kind of tools you stay with. But one thing to remember, no software or service is that 100% reliable!

You have to wait for more time if the password was strong enough (over six characters)! It could be days, weeks or months! Please keep this in mind.

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Kawhi Dumingz
Kawhi Dumingz

Written by Kawhi Dumingz

Tech content writer & blogger who’s passionate about computer software and hardware.

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