How to determine which program to use to open a file with an unknown extension. How can I find out the file extension if it has been lost? Find out file extension without extension

Has someone sent you an e-mail with a file you don't know what to do with? Have you downloaded the file and have no idea what it is for? How can you open a file with this extension? You can find answers to these questions in this article.

Since the days of MS-DOS, so-called extensions have been used to distinguish individual files. Previously, extensions were used three characters behind the dot, but today this restriction is no longer valid. Some operating systems, like Linux, don't need extensions at all. The file command is used to identify files on these systems, where the parameter is the name of the file - later you will learn something about its contents.

Nevertheless, extensions in these systems can appear, this can be in the case of an attachment to an e-mail or a file from the Internet. The purpose of the extension is to distinguish between files by their content. At first glance, this is how you can determine what the file will contain. For example, you can define that the .txt file will contain text, .jpg - a picture and.avi, of course, video. And what eg. Bz2, .7z, .lha, etc .. Don't know? Read on to find out how to determine this.

How do you determine which file it is?

The first problem you may encounter is that the extension of this file is not known to your system and the system will ask in which program the file should be opened. If the extension is unknown to the user himself, you need to start searching on the Internet. Some use a favorite search engine like Google, or use some of the specialized sites directly. Thanks to them, they will find out which file is in question and which program to look for. Some sites dealing with extensions:

File extensions (http://www.file-extensions.org/)

This site offers a simple search by file extension, initial letter, or you can browse extensions by purpose. If you find your extension, you will find out and detailed information about this format, as well as in which programs this file can be opened.

FileInfo.net (http://www.fileinfo.net/)

This site offers the same functionality as the previous one with a difference, which does not show other possible extensions for this format... Unlike the previous solution, here you will also find the corresponding programs for the operating room. Windows systems, Mac OS a Linux.

File extensions(http://www.pndesign.cz/pripony-souboru.php)

Czech similarity to previous sites. Unfortunately, you will not find a lot of information here. Still, the basic information about this extension is here.

And yet, if it doesn't work out?

The extension can be easily changed and searches for the extension will not necessarily lead to the correct goal. I ran into an extension change for one user who could not play a movie because his extension was unknown for the installed player (.mp4). Then the extension was changed to .avi and his favorite player played the movie. This solution is still not entirely suitable, so I do not recommend it. If someone has already done this, the solution may be different online services for identifying files. Among such online services, there are, for example, the following:

iConv (http://www.iconv.com/file.htm)

Offers an interesting online service where you just need to upload a file. Subsequently, the page will "tell" you what this file contains. Unfortunately, the information from this service is too modest. So its use is only indicative. It can be used only if the format has been significantly changed, i.e. the .txt file is actually a video.

Online TrID File Identifier (http://mark0.net/onlinetrid.aspx)

Here you can again upload your file, about which nothing is known. This service will provide you with important information about the file. Unlike the previous program, this one provides more information.

What if there is no internet? TrID

The Online TrID File Identifier project also has an offline version in the form of a program that is controlled from the command line. This can be a plus for one, and a minus for another. And this program will be able to determine what the file actually is, it uses not only the extension. The content is determined by examining and comparing the structure of the data array, so identification for small files may take longer than for the next program.

File

Again simple program which is managed via command line... As a result of the program's work, you will receive information about this file in the form of type and meta data. In this case, you can find out, for example, the name of the author of this document. Identifying large files, in terms of time, is still more difficult than in the previous case.

A program for determining the extension of unknown files by their content.

Let's see what this program can do.

Installing FileType Verificator

Download the program from the link and unpack it to a convenient place. We go into the folder and run the installer. The installation process itself should not cause any difficulties, just click the "Next" button, tick the "I accept the terms of the agreement" box and continue to click "Next", "Install" and "Finish".

Upon completion of the installation, we will see the main window of the program, which is still empty:

Defining Extensions in FileType Verificator

Let's figure out how the program works. Using the "Add File" button, select which files we are going to rename.

Files are added through the standard window and then appear as a list in the main program window. For example, I renamed the extensions for three jpg images, and also took one real txt file:

As you can see, the program easily recognized pictures disguised as text. To put everything in order, select the files that we are going to rename with checkmarks and press the "Start Renaming" button.

By clicking on the button, we will see the program warning:

If we have no doubts about our actions, press "Rename" and see the result. If the renamed files disappeared from the program list, then the renaming was successful. Please note that the program included the old, incorrect extension in the file name (that is, for example, there was primer1.txt, but it became primer1.txt.jpg).

How easy it is to replace the old extension with a new one, I unfortunately did not find. Perhaps this has some kind of secret meaning, like saving information about the old extension, but it seemed to me not very convenient.

Additional Tools FileType Verificator

In general, according to the main properties of the program, this is everything. The rest of the buttons and settings are secondary or provide a cosmetic effect, such as highlighting files different types different colors, view properties and contents of files.

Well, and perhaps, if there are a lot of recognized files, the tools from the "List" menu may come in handy.

These tools will help you select many files at once for later renaming.

Let's summarize:

Advantages and disadvantages of the program

does an excellent job with his duties;
supports Russian;
works very simply.

does not replace the extension with a new one, but assigns a new one after the old one;
there is no separate Select All button on the toolbar.

conclusions

The program is worthwhile, it is easy to install, renames well, works correctly, no serious shortcomings have been identified.

P.S. It is allowed to freely copy and quote this article, provided that an open active link to the source is indicated and the authorship of Ruslan Tertyshny is preserved.

P.P.S. There are programs on a similar topic, for example this

Have you ever received on email or through other communication channels files without an extension? Such files look like a white icon, which indicates that the system does not know which program to open it.

In response to an attempt to open a mysterious document, Windows will offer you to choose a program yourself from the list.

This "behavior" is due to the fact that operating system analyzing file extensions, compares them with the desired program and assigns them the appropriate icons so that not only the machine, but also the user understands what type of information he is dealing with. In our example, the system thinks that the file we are trying to open has the extension .9, which is not in its directory, and therefore issues such a message.
How is it that the resulting document or other kind of file does not have an extension? Most likely, the fact is that your interlocutor, while editing the name of the document, simply overwritten that very extension.

How to open a file if there is no extension, but the contents of the file are known

It is good if we know the sender and know what type of document was sent to us. For example, we know for sure that this file is a table. In this case, we simply select a spreadsheet editor from the list suggested by the system and safely open our file.

To do this, hover the cursor over the file, press right key mouse and in the context menu select the item "Open with"

Then, click "Use the application from this PC"

Scroll through the list of programs to the end and select the item "Find an application on this computer"

You will be prompted to search the desired program in folder with installed programs Program Files. If the package office programs installed on your computer, then you can find the corresponding folder. If you are using free software, then instead of Microsoft Office maybe there will be folders like Libre Office or Open Office

Another option is to add the extension manually, e.g. xls, if we are talking about an Excel table.

Hover the cursor over the file, open the context menu with the right mouse button and select “Rename”.

Then carefully, after the point, enter the correct extension and press Enter to save the changes. We agree with the warning, click "Yes".

But what if there is no way to specify the file type?
Needless to say, if the sender is unknown, then you should not try to open attachments under any circumstances, so as not to expose your computer to a virus infection. But if the file is obtained from a reliable source and does not cause any doubts in you, then you can find out its type only by analyzing its contents.

How to determine the type (format) of a file by its content

Any file, be it Text Document, an image, or something else, is nothing more than a code structured in a certain way, understandable by a program intended to read and / or edit it. As mentioned above, the operating system chooses a program to open a file based on its extension. It is written after the name of the file, separated by a dot. By analyzing the image1.jpeg file, where.jpeg is the extension, the system understands that this is an image, and to read this file, you need to use an image viewer. By changing the file extension from .jpeg to, for example, .txt, we certainly won't turn the image into a text file, just the system will try to open it with text editor, as a result of which we will see only a set of symbols. Obviously, the file format (type) is determined not by the extension at all, but by its content.
To see in the contents of a file signs indicating that it belongs to a certain type, we will use a hexadecimal editor, for example, Hex Editor or an online service.
Whichever jpeg image we open, we can observe the similarity in the first three pairs of numbers, which indicate the file type.

It remains to find what format the encoding corresponds to. But you can not complicate your life and use a ready-made application that will do all the work. In our example, this will be File program Type Verificator (FTV). It is freely distributed and has a clear Russian-language interface.
Finding out the file format with this program is as easy as shelling pears. Click the add file button,

select the desired file through the explorer window,

and we see the file format corresponding to its content.

The program provides the ability to rename a file by changing its extension. To use this function, click "File" -> "Start renaming ..."

And in the window that appears then, click apply, if you agree with the option proposed by the program.

After such manipulations, the problem file will be opened by the desired program.

All users who work in the operating system constantly open certain data. In most cases, there are no problems with their launch, it is enough use any from launch methods:

double click with the left mouse button;
highlighting the icon with the mouse, the tab button or arrows, and then pressing enter;
right-clicking, and then choosing: open or open with.

This is the case in most cases, because the system has a default mapping for the most common files, and it knows which program to use to open items with similar extensions.

However, sooner or later, the user will be faced with the fact that the system will not be able to recognize some data and will give a similar message.

Here you should pay attention to the extension, because in the future you will have to search and install an application in order for the OS to learn how to work with them. The extension can be recognized in another way. For example, you can right-click on an element and select its properties, in the main window you can see the type, you can also go to the tab In detail and see it expand there. The extension itself is written with a dot after the name.

In this case, the application is already mapped to the extension and you can see it at home page, in the case of an unknown element type, the application will not be displayed. You can just turn on display extensions in the explorer. To do this, go to the control panel, then go to the folder settings and uncheck the required item.

Which program to open the file

Now that the user knows the type, you can start opening it. Of course, the easiest way is to copy the type name into the search bar and write "How to open", however, there is an opportunity to get to not the most reliable sites. The following are the types that used most often, as well as utilities with which you can work with them.

Rar, 7z - these are archives and can be opened by archivers that are similar in name to the. Winrar, 7zip - they can also work with most other archives.

Pdf can store documents, drawings, pictures and many more different data. You can open them with foxit reader or acrobat reader.

DJVU also represent scanned documents, often entire books are stored in this format. You can open it using the DJVU reader, in some cases the data is not matched, then you should run the utility, select the file-open and specify the path to the element.

Flv, mkv, avi, mp4 and so on are video data... Some can be opened through a standard player, while others will have to download another player. In any case, it will be better to download and install K-Lite Codec Pack... It is capable of playing almost all known video formats.

Wav, mp3, etc are audio format files, any player, even the built-in one, is suitable for playing them. For some more specific types, you will have to search and install additional utilities.

Fb2, mobi, this type includes electronic books ... They are understood by most of the readers and programs for reading books on the android. In Windows, you can install the FB2 reader extension and open it through it.

Docx, these files are capable of open utilities Microsoft Word 2007 and newer. Before this version, there was the .doc type, the old format is opened with new utilities, and the new one, of course, not with the old ones, so you should pay attention to the office version.

Xls, xlsx - maps to Excel 2007 and newer utilities. Junior versions only open the first format.

Ppt - in this format presentations are stored created in powerpoint.

V txt format are kept text files , which can be easily opened with a regular notepad.

Files with an unknown extension

A situation may arise that desired file not listed above. In this case, you will have to look for the necessary utilities through search engines or you can use one of the data type search services. For example, http://formats.ru, the user will need to enter the type and click on search. Further, the site will show the application that is required to run such an extension.

You can still use the service http://www.filetypes.ru/. Here you can search by file type or just type the extension into the search bar. The site will show not only the program you need, but also provide a download link.

To view video information, even in not the most common format, it is worth using video players, for example, the one presented on the page https://play.google.com/store/apps/details?id=org.videolan.vlc&hl=ru.

To unpack archives should be used by everyone that is also available in the mobile version.

Working with exe format

To open and use standard windows executable files exe will have to use one of the emulators.

BOCHS

First you need to download the application (https://trashbox.ru/link/bochs-android), and give your permission to install from unverified sources and install it. In addition to it will need to download the SDL_for_BOCHS.zip archive, the contents of which are the utilities needed for emulation. The user will need create at the root sdl directory and extract the contents of the archive into it. Next, you need to open the marked file in this directory.

AND write inthere ata0-slave: type = disk, mode = vvfat, path = / sdcard / HDD, journal = vvfat.redolog

You will also need to add the HDD directory to the root, all files should be placed in it. The device should now be restarted. After launching the application, to call the keyboard, you need to click on the lower left corner, and to emulate the pressing of lkm / pkm, you should use the volume keys.

QEMU

In this case, you should download SDLapp.apk, install it, and then download and install the Qemu Setting utility (https://trashbox.ru/link/qemu-android), in which you can easily configure all the system parameters without a lot of unnecessary actions.

DosBox

There is also such an excellent program as dosbox (https://trashbox.ru/link/dosbox-manager-android). She emulates command line and will allow you to run old DOS games and some other files.

What is the file extension?

File extensions is a kind of metadata. Typically, the file extension is used to denote the kind of data that can be stored in the file. Thus, a file extension is a sequence of characters that are used to identify the file format. Typically, the extension is separated from the base filename by a period. In early operating systems, the extension was limited to only three characters, but this limitation was later removed. Some files have multiple extensions that follow each other (for example, .tar.gz). Operating systems automatically match the extensions of certain files and programs designed to work with those files. And after such a mapping, the operating system will automatically open a file with a specific extension in the program that was mapped to it.

The file extension and name are separated from each other using a period, for example, index.html, where html is the file extension. Looking at the file extension, you can immediately tell what kind of file it is - text, picture, sound or program. File names may or may not have extensions. Computer users have some conventions for using standard extensions in filenames. Programs that generate different types of information usually assign standard permissions to the names of the files in which the information is stored. And by the look of this permission, the user can conclude with which program the file was created.

How to find out file type to expand it?

The following are ways to determine the file type by extension:

Termin.narod.ru- this site contains an extensive list of file extensions, to find the extension you need, you only need to select the letter with which it starts.

Uic.vsu.ru- the most popular extensions are collected here.

Filetypes.ru- this site contains the most complete search database for file extensions, you just need to enter the required extension into the form.

Filext.com- site on English language where you can also get information about the file extension by entering it into the form.

Another way is the program Know Extension Pro, which determines the file type by its extension. The English database contains more than 23,000 file types, the Russian database - 2235. The program can work from context menu and in compact mode. You can add your definitions to the extension base. The program is distributed free of charge. The purpose of the program is to determine its type by the file extension. The program will be useful both for novice users who want to know the purpose of certain files, and experienced users who want to create their own knowledge base, since using this program you can add new data to the database.

To start working with the program, simply drag the file of interest to the special field in the program window, or select the File - Open menu item. If such an extension is contained in the database, its description will be immediately displayed on the screen.