OpenOffice.org: When it comes to freeware office softwares, nothing can beat OpenOffice. Apart from other components like a word processor, presentation creator, OO.o comes with a a powerful spreadsheet with all the tools you need to calculate, analyse, and present your data in numerical reports or sizzling graphics.
It has some impressive features like Advanced DataPilot technology that makes it easy to pull in raw data from corporate databases; cross-tabulate, summarise, and convert it into meaningful information. Natural language formulas let you create formulas using words (e.g. "sales - costs"). The Intelligent Sum Button inserts a sum function or a subtotal automatically, depending on context. There are wizards to guide you through choosing and using a comprehensive range of advanced spreadsheet functions. Styles and Formatting makes it easy to apply flexible cell formatting options, including freely rotating contents, templates, backgrounds, borders, and many more. You can be your own spreadsheet expert thanks to templates with built-in functions, allowing you to concentrate on your real work. Calc is the best replacement for Excel
Abykus: Abykus 2.0 is an easy to use spreadsheet program designed for both business and scientific applications. The program includes a statistics wizard, as well as over 190 built-in math, trig, matrix, financial, date, time, string, coordinate geometry, and 3D graphic display functions. Up to 32 separate, 65534 row by 255 column, worksheets can be loaded and accessed at one time.
To make the program easier to use, the familiar "A1" naming convention (used to reference other cells) has been replaced with a notation that uses numbers, algebraic expressions, or even other cell addresses to represent the row and column numbers of any cell being referenced within a formula. This new notation is not only more intuitive, it is also more powerful as it makes it possible to create dynamic cell addresses within formulas that can automatically reference different cells, as values on your worksheet change.
In addition to dynamic cell addressing, Abykus allows you to store multi-value data types (called cell objects) in any cell located on your worksheet. When used, cell objects can be assigned up to 8191 individual values, saving valuable real estate on your worksheets, as well as reducing the amount of overhead needed to manage your data. Cell objects can be used to represent anything from a simple table to a polygon comprised of hundreds of coordinate pairs. Cell objects are continuously updated as changes are made to your worksheet and can either stand alone or be used as building blocks to form other cell objects.
Abykus supports right from Windows 95 to Windows Vista. Abykus does not come with a bunch of files and associated dll's. It's is a single executable file and requires less than 3 megabytes of disk space
Spread32: Spread32 is a tiny spreadsheet program that supports 256 columns x 65536 rows x 255 sheets, formulas with over 300 functions, sorting with multiple keys, freeze panes etc. It may not have all the bells and whistles of its beefier cousins, but it is an excellent choice if you just want to fire up something instantly for some quick-and-dirty calculations. Ofcourse, you can't expect more from a less than 500KB program. But then, not everybody uses advanced spreadsheet features. Unfortunately, the program has gone shareware, but the last freeware version is available in the Floppy Office bundle.
Download and extract the Floppy Office ZIP package to a temp folder. Then extract the contents of spread32.zip to a folder of your choice. Launch the program by double-clicking on Spread32.exe. You can also directly download the file from here.
CleanSheets: CleanSheets runs on Java and is the first spreadsheet application that is both extensible and platform-independent. It features a formula language that closely resembles that of Microsoft Excel, and extensions for aiding end-user programmers develop correct spreadsheets. A nice, extremely light application for simple spreadsheet functions.
Update (April 3, 2013): Kingsoft Spreadsheets 2012 is another great alternative to Microsoft Excel. . Open *.xls and *.xlsx format files made by Microsoft Excel; create and save spreadsheets in *.xls and other formats like *.et.
Convert Spreadsheets workbooks into PDF files - Export spreadsheet to PDF files directly within the program.
Multiple Tabs interface makes it more convenient to switch between several workbooks. It allows you to open many workbooks page on a single window task to optimize your window sequences.
A great number of formulas are provided for both daily office work and professional business such as Sum, Average, V lookup, Mid, TRIM, TEST, etc.
Shortcut functions to quickly handle data - These functions include an auto filer, sort ascending, sort descending, auto sum, and more. You can easily edit data by using them.
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