Here is the eleventh edition of our Weekly Office 2.0 Roundup. Today, we will review 10 online spreadsheet editors, from ajaxXLS to Zoho Sheet. We will identify some unique features that might help your own selection process, and you will get a chance to cast your vote for the best online spreadsheet editor.

With the help of many contributors, we completed the Spreadsheet section of the Office 2.0 Database. From the 10 players we identified for this article, eight are actively developed by legitimate companies, and two are virtually dormant, if not abandoned (Num Sum and Numbler).

Functionality
From a functionality standpoint, an online spreadsheet editor lets you build simple spreadsheets directly from your web browser. All the applications we reviewed for this article have been implemented using AJAX, while ThinkFree Calc also provides a cool Power Edit mode implemented in Java. Most of the applications we reviewed support the usual sharing and publishing of spreadsheets, while a few, such as EditGrid, Google Spreadsheets, Zoho Sheet support the collaborative editing of the same spreadsheet by multiple people at the same time (real-time update). All the applications we reviewed support the import and export of spreadsheets, usually using Microsoft Excel's .xls format. About half of the applications we reviewed provide an open API, but only a couple support custom branding and custom domains. About half of the applications we reviewed provide charting capabilities, with EditGrid offering the most comprehensive set of chart types. EditGrid and Zoho Sheet also provide the ability to embed data dynamically fetched from any public web site.

Ease of Migration
Migrating from an offline spreadsheet editor such as Microsoft Excel to an online alternative is trivial if your spreadsheets do not make use of macros and pivot tables, yet virtually impossible if they do. Also, large spreadsheets with tens, if not hundreds of thousands of cells won't easily load into any of the applications we reviewed, at the exception of ThinkFree Calc when used in Power Edit mode. At present time, none of the vendors we talked to have expressed interest in implementing support for macros and pivot tables. The technology used by Microsoft Excel for macros is tightly linked to the underlying operating system, therefore is very difficult to replicate with a platform-agnostic online tool running within a plain-vanilla web browser. Nevertheless, a subset of Microsoft Excel's macro language could be supported in the future, and we expect EditGrid, ThinkFree, and Zoho to lead the pack in this area. As far as pivot tables are concerned, both technical and legal challenges are in the way. At a technical level, the processing of pivot tables can be very taxing from a system resources standpoint, and the JavaScript language used by AJAX applications creates severe performance limitations. At a legal level, the technology used by Microsoft for pivot tables supported by Excel appear to have been protected by a large number of software patents, which could make the implementation of online alternatives quite challenging, if not impossible.

Price
At present time, all the applications we reviewed offer a free edition, while about half of them also provide a commercial edition, priced from $2.50 to $25.00 per user and per month. We believe that such a pricing model will generalize itself moving forward, and that users will be willing to pay anywhere between $2.50 to $10.00 per user and per month for premium editions.

Alternatives
The main alternative to an online spreadsheet editor is a specialized tool dedicated to the management of specific data sets: an expense tracker for managing expenses, a project manager or a task manager for managing projects and tasks, or a time tracker for managing time sheets. An online database could also be used to manage any structured data, especially one that provides a spreadsheet view with mass editing capabilities, like Dabble DB for example.

Top 10 Players
Several online spreadsheet editors do make use of HTTPS, therefore the Alexa ranking is not as reliable as we would like it to be. Nevertheless, and according to this ranking, we can extrapolate a Top 10 list of players in the space, which is somehow corroborated by their respective Google PageRanks and by the data we gathered from EditGrid, ThinkFree, and Zoho for the Office 2.0 Audit Service.

Editor's note: Alexa only ranks primary domains, not subdomains. Therefore, traffic generated by Zoho Sheet is lost among the traffic generated by all applications provided by Zoho. According to Alexa, Zoho Sheet accounts for 4% of Zoho's overall traffic, therefore it can be assumed that Zoho Sheet is one of the most popular online presentation tools currently available.

Quick Reviews
There are only 10 applications in our database, so all of them got a review.

ajaxXLS: ajaxXLS, which is part of the comprehensive suite of applications provided by ajax13, is a simple spreadsheet viewer, complemented by an editor currently under development. It only runs with Firefox, but compatibility with Microsoft Excel and OpenOffice.org allows it to preserve all common cell formatting categories such as text styles, decimals, currencies, dates, and times, as well as formulas, backgrounds and borders from the original documents.

EditGrid: EditGrid is probably the most advanced and most polished AJAX-based spreadsheet editor we have come across for this roundup. EditGrid supports real-time update, which allows users to see changes immediately when someone is editing the same spreadsheet, and provides the ability to lock ranges of cells. EditGrid also supports remote data embedding, and provides 36 types of good-looking charts. EditGrid also supports advanced access control, post-to-blog, chat, version control, and over 500 built-in functions.

Google Spreadsheets: Google Spreadsheets is part of the Google Apps offering, and provides a streamlined way to view and edit simple spreadsheets. It was one of the first online spreadsheet editors to support real-time update and chat, which were first demonstrated at the Office 2.0 Conference.

Num Sum: Num Sum is a simple online spreadsheet editor that supports sharing, publishing, and syndication of spreadsheets, as well as posting to a blog. Unfortunately, Num Sum has not been updated for more than a year now, therefore users looking for a long term solution should really consider other alternatives.

Numbler: Numbler is a simple online spreadsheet editor that supports sharing and real-time update of spreadsheets, with the ability to lock ranges of cells, and to reference cells from multiple sheets. Unfortunately, Numbler has not been updated since June 2006, therefore users looking for a long term solution should really consider other alternatives.

Sheetster: Sheetster is an online spreadsheet editor based on the ExtenXLS spreadsheet technology, an easy-to-use spreadsheet automation API that allows you to read, modify and create spreadsheets from Java applications. Even though fully functional, Sheetster should be viewed more as a proof of concept for ExtenXLS, rather than a standalone product directly competing against the other applications we reviewed for this roundup.

ThinkFree Calc: ThinkFree Calc is probably the most advanced online spreadsheet editor currently available. As any other component of the powerful ThinkFree suite, ThinkFree Calc provides a Quick Edit mode built in AJAX, and a Power Edit mode built in Java. The Power Edit mode can be considered as a clone of Microsoft Excel 2003, minus macros and pivot tables. It provides the exact same features, and the same familiar user interface. ThinkFree Calc is also the only online spreadsheet editor that can be used for very large spreadsheets that contain tens or hundreds of thousands of cells.

wikiCalc: wikiCalc is an online spreadsheet editor developed by Dan Bricklin, co-creator of VisiCalc, the very first spreadsheet editor. It combines some of the ease of authoring and multi-person editing of a wiki, with the familiar visual formatting and data organizing metaphor of a spreadsheet. It can be easily set up to publish to basic web server space accessed by FTP, or run on a server and be used with nothing more than a browser on the client. It is also integrated with Socialtext, one of the best enterprise wiki solutions currently available.

Xcellery: Xcellery allows users to share and edit Microsoft Excel spreadsheets online. Unlike other online spreadsheet editors we reviewed for this roundup, Xcellery doesn't try to replace Microsoft Excel, but extends it, by allowing a single spreadsheet to be shared and synchronized across multiple users in real time. For users who do not have a copy of Microsoft Excel installed on their computer, Xcellery also provides a powerful browser-based AJAX editor. Xcellery is compatible with a wide range of features offered by Microsoft Excel, but currently does not provide support for charts.

Zoho Sheet: Zoho Sheet is one of the most powerful AJAX-based spreadsheet editors currently available. It is fully integrated with the comprehensive suite of applications offered by Zoho, supports real-time update, remote data embedding, as well as sharing, publishing, and syndication of spreadsheets.

Personal Favorites
I currently use ThinkFree Calc for complex spreadsheets that are based on existing Microsoft Excel templates, and Zoho Sheet for simpler ones built from scratch. I am also considering using EditGrid for the production of charts to be embedded on various websites.

What's Missing
Beside support for macros and pivot tables, integration with Salesforce.com would be fantastic. A typical use case would be to dynamically embed data produced by Salesforce.com reports into a spreadsheet, merge it with data provided by third-party services, then produce charts from it.

Best Online Spreadsheet Editor
Now that we know what's out there, it's time for a vote:

Note: if you cannot see the voting form, please follow this link.

Final results will be announced next week on Your Office 2.0 Setup and as an update to this post. In the meantime, please help me build next week's roundup on Weblogs. You can use this form courtesy of Wufoo for suggesting new applications, or providing additional information about existing ones. I would also welcome ideas for domain-specific criteria that could be used for evaluating the players on our list.

See you next week!

Disclaimer: I serve as an advisor for ThinkFree and Zoho.