Certainly, the Excel spreadsheet editor included in any Microsoft office suite is the most powerful tool for performing simple mathematical calculations, and for automating more complex tasks related to algebra, geometry, trigonometry, not to mention the possibility complex use of tools, for example, for accounting with reference to databases. Alas, almost all versions of Excel are paid (in fact, like the office suites themselves), and until recently, most users increasingly thought about installing Excel analogues, which would not have to be paid for and which would have the same (or even greater) capabilities compared to the original. Such programs exist! Below it is proposed to consider some of them in a small volume, since most of the functions and actions are exactly the same (however, like the menu and interface).
Excel vs… Excel
First of all, it’s worth saying that now it’s not possible to look for an analogue of Exceleven in principle.

This is due to the fact that the standard application can be installed completely free of charge from a special Microsoft repository on the technical support site. Almost all the Office components included in the main package are presented there, but you can download and install not the entire set, but only those programs that are really needed for everyday work.

In addition, just recently in the world media there was information that the developers of the Microsoft office suite took an unprecedented step, saying that the new Office 2019 starter set will be absolutely free (unlike all previous modifications, Pro versions and commercial cloud service Office 365). Thus, the main question concerning the free purchase of the editor disappears by itself. But after all, among users there are a considerable number of those who do not like Microsoft software products. What should they choose?
A free analogue of Excel in the OpenOffice.org suite
As you know, as one of the most successful and advanced alternatives to "Microsoft" developments, most experts call the packages distributed free of charge under the GNU license that are part of the OpenOffice.org set.

Besides the fact that there is a perfect analogue of "Excel" in the form of the same Calc editor, for the package itself, enthusiasts can use open source code withthe purpose of supplementing or improving the programs included in its set. The only limitation of the spreadsheet application is that it does not support running native macros created in the original Excel based on the Visual Basic language, but it can work with native Basic tools that are slightly different. Otherwise, the actions performed, the setting of formulas, and the cross-support of related office components are almost equivalent.

Note: exactly the same editor and with the same name can be found in the LibreOffice suite.
Analogue of "Excel" for "Windows" in the WPS Office package and other no different editors
As the name suggests, this is another alternative office suite. Among its components, you can also find an analogue of Excel, which in this case is called Spreadsheets.

This application uses the look and feel of the original 2013 Excel as its main interface and has nothing to do with the 2003 version. As for the tools, menus available for performing actions and operations, they do not differ from MS Excel at all.
If we consider other programs similar to Excel, which are not particularly different from the Microsoft office applet, we can separately note good editors like Symphony Spredsheets from the Lotus package, PlanMaker from the SoftMaker Office suite, etc. Even at first glance on the appearance of these tabulareditors to catch the difference with the original Excel is very difficult (perhaps only by the names of programs that are displayed in the window title).
Chrome Browser Cloud Tools
As you know, one of the largest and most serious competitors of Microsoft - Google Corporation - also does not lag behind and, if it does not create something new in the field of office software products, then at least it tries to introduce its own applications in all spheres.

In this case, we are talking about an analogue of "Excel" in the form of a cloud application "Spreadsheets", which is available directly in the Chrome browser as an extension installed initially. In a sense, this applet can be called a competitor to Excel from Office 365, since it works on the same principles of organizing access through the cloud. Only this product is completely free, and to use it you just need to have a Google account with registration in the Gmail mail service.
Android built-in tools
Since we are talking about Google products, exactly the same analogue of "Excel" for "Android" (the "Spreadsheets" application) can be found in all the latest modifications of the operating system itself in a pre-installed form. Only the applet itself is a stationary, not a cloud application, and you can work with it in the same way and using all standard functions and features, as with the original without mandatory access to the Internet. Connection may be required only in order to savea document in the cloud (Google Drive) or sync files between different devices that can use a Google account.
Additional applets for mobile systems
Finally, one of the good alternatives to Excel for mobile devices is the OfficeSuite package, designed for the Android system environment.

The only drawback of the whole set is that it is constantly offered to upgrade the free version to the Pro modification, having previously tried it in operation without payment within seven days from the date of installation. If this reminder does not bother you, you can simply ignore it and use any component of the package (including the spreadsheet editor) for your needs for an unlimited period.