Diff Doc review
A capable Windows comparison tool with broad format coverage and a high one-time price.
Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026
Diff Doc is a Windows desktop application from SoftInterface, Inc. for comparing documents, files, and folders. It covers PDF, Word, Excel, PowerPoint, RTF, HTML, XML, plain-text, and other file types, with paragraph-, word-, and letter-level difference detection. Side-by-side and unified views, customizable highlighting, and report generation make it suited to individuals, legal and accounting teams, and business workflows that require repeatable comparisons.
Pricing uses perpetual, one-time licenses rather than subscriptions. Diff Doc Standard costs $299.95 one time and includes text file comparison, folder comparison, HTML/XML scripting, and a perpetual license. Diff Doc Professional costs $499.95 one time and adds PDF comparison, Word, Excel, and PowerPoint comparison, plus RTF, HTML/XML, and WordPerfect comparison. A 30-day free trial is available, but there is no free plan. The Professional tier is the relevant choice for teams working across PDF and Office formats, while Standard fits narrower text-focused workflows.
The product’s strongest differentiator is its combination of detailed comparison controls and workflow output. Users can customize change highlighting, compare folders, generate Word, HTML, text, or CSV reports, and run comparisons through command-line automation. Worldox and ActiveX COM integrations extend its fit for document-management and repeatable business processes. Diff Doc is a practical choice for Windows users who need broad format coverage, report formats, and automation in a desktop tool. Organizations requiring a web or non-Windows deployment should consider a different product, and buyers with occasional comparison needs may find the one-time cost difficult to justify.
Diff Doc pros and cons
- Where it wins
- Compares PDF, Office, RTF, HTML, XML, and plain-text files
- Detects paragraph-, word-, and letter-level differences
- Generates Word, HTML, text, and CSV comparison reports
- Where it doesn't
- Windows desktop deployment limits platform choice
- No free plan is available
- The one-time starting price is relatively high
Diff Doc fact sheet, pricing and score →
Advertiser disclosure: iTechGuides is reader-supported. Vendors can pay for top positions in our rankings and for a place on other products' pages, and we may earn a commission when you click some links. Bought places stand at the number bought; this page and our disclosure say so. Paying vendors may get a fuller, more detailed review from our editors, and that review can change their score. How we rank.
Last updated · How we research and update