Very few applications are in the “save your job” category. Task managers keep you organized; Apple iCal ( ) helps you stay on time for meetings. But Araxis Merge 2009, a powerful file comparison utility, can get you out of a tight spot at work. The name is a slight misnomer: its purpose is to check the contents of two files and reveal the differences between them. You can then merge one file into the other if you choose. The professional edition I tested actually lets you compare three files or folders, while the standard edition lets you compare two.
For example, if a law firm needs to compare the historical record of a document to a newly updated file, a clerk can quickly see the differences between the files via color coding. Or a journalist who has several drafts of an article can see the changes between document versions. There’s even a way to see minor differences between two images by inspecting the binary code. (Currently, Merge only allows you to see that the images are different, but not to make corrections.) For developers, comparing code changes becomes easy and intuitive, as opposed to very complex, frustrating, and time-consuming.
Merge has some tough competition, though. There’s Deltopia DeltaWalker Oro, a less expensive option with similar features, and Softhing’s File Compare 1.1, a more limited program that’s free. Apple includes a basic file comparison program called FileMerge with its developer toolkit. But Araxis Merge is easier to use than the other commercially available choices because it runs natively in OS X (DeltaWalker requires a Java run-time environment and runs on Eclipse—a universal toolset for development), runs fast, and supports a cornucopia of file formats. If you’re a coder, reporter, photographer, or just someone who has a lot of files and needs to compare them, Merge is a powerful ally.
File comparison tests
For comparing text documents, Merge provides two windows in a side-by-side view. Green blocks help you find key differences, such as a single word or even just an out-of-place comma. It would be nearly impossible to visually compare two long documents in Microsoft Word, for example, by scanning through every line for a slight variant.
Developers can see differences between lines of code in XML and HTML files. I tested a series of HTML sites and found several code problems: in one older HTML file, a navigation bar pointed to the wrong HTML file, and an image link was spelled wrong.
When you find differences between files, you have a few options—you can just type in text to correct one of the documents, or you can merge changes from one document to another by clicking a small merge button next to each highlighted comparison. Or you can copy and paste text into the windows—the quick method. Merge supports native Word and Excel formats (including the latest 2008 versions), OpenDocument 1.2, Adobe PDF, and Rich Text Format. It also supports PowerPoint and HTML files.
Once you locate changes between documents and save the results, you can have Merge generate a report showing the differences between the files to send to colleagues. Merge can even generate an HTML file you can post to a Web site, where co-workers can then see file comparisons for themselves. The program supports Perforce and Subversionplug-ins, tools for source code control.
I tested document discrepancies in a 200-page novel for young adults that I’m writing. In the vein of job-saving practical use, I discovered two documents in which I had started writing new sections. Even in a manuscript of over 100,000 words, Merge quickly showed me where the documents differed, and I added new sections into one of the documents by clicking on a merge button. If I had archived one of my files with Time Machine, Merge supports a comparison between a current file and an earlier revision in the Time Machine archive, a handy addition.
Performance is remarkable. Merge offers two different versions, one for Tiger and one for Leopard. I used the Leopard version on a Mac mini and on an older iBook and experienced no crashes or slowdowns. Araxis says Merge will run even faster on newer Macs with 64-bit processing, because the memory management for large files works more efficiently.
Merge also supports folder comparisons so you can see the difference between, say, your desktop computer files and a folder on your laptop, or between network drives. For developers, this means you can copy a series of images and HTML files, or a vast collection of XML files, and see within a few seconds which folders are missing files. I can imagine a serious developer using Merge every day as a sanity check on not only their code but on file libraries, and using it for team-based collaboration as well.
Tech support for Merge—offered only via e-mail—was extremely fast and helpful. I had problems with the initial download (the disk image file was corrupted and prevented install—even after downloading a new file). The support suggested removing all previously downloaded files, which worked like a charm. I also posed a series of questions to Araxis support and received comprehensive replies in just a few hours. If you’d rather skip tech support, Merge has a comprehensive help system with context-sensitive help for every menu item, dialog, and control.
Merge is not perfect, however. I’d prefer a tabbed interface so I could have multiple files open for comparison and just click on the tabs I want to see. The interface for Merge is not exactly stellar: it looks like a tool hardcore Mac developers would love, but not the average business user comparing PDF brochures. I would prefer a more Mac-like look and feel with icons, buttons, and shaded windows. And, if all you need to do is compare raw text (but not any other kind of document), FileMerge or File Compare will do the job less expensively without any extra features, such as plug-in support.
Macworld’s buying advice
Merge is worth every penny if you need to compare rich or long documents. If you’re a developer, it effortlessly finds code discrepancies and allows you to correct them. As a writer working on very long documents, there’s no other tool I would consider now. In just a few minutes, I found very specific word and punctuation differences in a 200-page document, a task that would have taken me hours or even days to do manually. I highly recommend Merge 2009 as an indispensible tool for serious Mac users.
[John Brandon is a 20-year veteran Mac user who used to run an all-Mac graphics department.]