Programs and applications may automatically create folders while you’re working on your computer. For example, while in Photoshop, you may have noticed a new file appear with the extension “.tmp.” However, what is a .tmp, and how is it used? There are a few reasons a program may create a .tmp file, including data backup, performing communications between processes, and breaking up information into digestible segments. This article explores these temporary file types, as well as why they’re created and how you can open and remove them safely.
.tmp Files Explained
The extension .tmp is short for temporary. Programs create temporary files to store and back up data. Programs may also use them as a cache for a program or an operating system. When working on specific tasks, temporary files can help create memory to prevent data loss.
Temporary or .tmp files are important because they have data that can increase a program’s effectiveness. Also, by using these “throw-away” files, your computer and its programs run faster because the temp files help gather information quickly. Temporary files may include text, photos, video, and other cached data. All of this information is related to the app you’re using.
For example, you may find that Excel, Word, and other Windows applications will create temp files if you have the AutoSave on. In addition, other apps, such as Photoshop, will make them. While you’re working, the software will create a .tmp file to save the application data on your hard drive. Should you experience a crash or otherwise quit a program, the temp file allows you to recover your document.

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Why Do Computers Create Temporary Files?
As we mentioned above, computers create .tmp files to store information, temporarily freeing up memory for other purposes. A program will also make them as a safety measure to prevent data loss when a program performs specific functions. Let’s look at the reasons why computers create temporary files in more detail.
To Save Memory
Your computer may need additional memory to store a document with all its edits and multiple versions. When this happens, some actions are unavailable while running various applications. If low memory and space are an issue, the application will create a new document containing all the data not being edited.
The app will move this information to a disk or the .tmp file. Moving this data will free up memory for edits and storage of a document currently in use.
To Prevent Data Loss
Sometimes, your computer may use .tmp files as a way to protect against system errors. This backup is how a temp file will ensure an original file’s integrity isn’t lost. For example, a file may become corrupted or lost if a power failure occurs. The creation of a temporary file will allow you to recover the document you were working on with minimal loss.
Where Are Temporary Files Kept?
If you’re having trouble finding your temporary files, try searching the following folders.
Windows
On Windows computers, most programs create their temporary files in a separate folder. You can find this folder by following the path: C:\Users\AppData\Local\Temp. You can also You can locate .tmp files using the command %temp%.
Mac
On a Mac, you can find .tmp files within a folder that is specific to the app. You can go to the folder from the Finder or search using the path ~/Library/Caches/. Once you’re in that folder, you should see all of the created .tmp files.
How to Open .tmp Files
Most temporary files aren’t meant to be opened, per se. However, that doesn’t mean you can’t. You can typically open a temp file using the same program that created it. For example, if Microsoft Excel created a .tmp file, you can change the extension to .xlsx and try to open it as a regular Excel file.
Unfortunately, it is not always easy to determine which app or program created the .tmp file, so you will need compatible software to open the file and view the contents. You can attempt to open a .tmp file from the Temp folder on your PC by clicking on the file. You will then be asked to select an app to open the .tmp file.

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You may be able to open .tmp files using word processing apps, media players, or text editors like Notepad on Windows or TextEdit on Mac. You may also be able to use browsers such as Intenet Explorer, Firefox, and Safari.
How Long Do .tmp Files Remain?
Most of the time, you can depend on .tmp files to be on your computer for a short time. Your computer will automatically delete .tmp files:
- When the program no longer needs it.
- After you close the program that created it.
- After you turn off your computer.
While your computer will likely delete most of them, not all .tmp files are automatically removed from your computer. Temporary files may remain if the code doesn’t include the instructions to delete itself or the application that created it crashes. Because this can happen, a build-up of temp files may accumulate on your computer. If this happens, temporary files block precious memory and disk space.
We should also note that .tmp files that programs have automatically removed may leave tiny bits of data behind. You can delete these data bits to clean them up and clear up space.
Removing .tmp Files
Yes, it’s safe to remove .tmp files you find on your computer. As mentioned, you can find all of the temporary files on your computer by going to a particular folder. On a Windows machine, you will find them under AppData\Local\Temp. You may also find them under \Windows\Temp. If you see that Windows hasn’t deleted the temp files for you, it’s safe for you to delete the files you find in either place.
On a Mac, you can find your .tmp files under ~/Library/Caches/. You can feel safe to delete the temp files you see here.
Making the Most of Temporary Files
If you see temporary files on your computer, remember that it’s not a bad thing to have files ending in .tmp. Some programs will create them if you have the AutoSave function on. They’re not malicious and once you quit a program, they’re likely to disappear. However, if they remain, it is safe for you to delete them. If you find a temporary folder while working, know that it’s there to be a backup for data loss and to help your computer run more efficiently.
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