Best STDU Viewer Alternatives in 2025
Looking for alternatives to STDU Viewer? In this comparison, we take a closer look at STDU Viewer alongside similar software solutions including STDU Viewer, SumatraPDF, PDFCreator, FlexiPDF, FreeCommander XE, Adobe Reader, PDF-XChange Editor, NAPS2, PDF-Creator, PDF-XChange Viewer and Adobe Acrobat DC.
Our detailed comparison table highlights key features, pricing, and performance of these leading solutions, empowering you to make an informed decision. Whether you're seeking robust functionality, user-friendly design, or cost-effective alternatives, explore how STDU Viewer, SumatraPDF, PDFCreator, FlexiPDF, FreeCommander XE, Adobe Reader, PDF-XChange Editor, NAPS2, PDF-Creator, PDF-XChange Viewer and Adobe Acrobat DC stack up to find the perfect software for your goals.
Platform Compatibility
 STDU Viewer
|
Windows, including Windows 10 |
 SumatraPDF
|
Windows, supports multiple versions |
 PDFCreator
|
All Windows operating systems |
 FlexiPDF
|
Windows and Mac |
 FreeCommander XE
|
Windows Vista, 7, 8, 10, supports 32-bit and 64-bit |
 Adobe Reader
|
Windows, Mac, Android, iOS |
 PDF-XChange Editor
|
Windows 7, 8, 10 |
 NAPS2
|
Windows Vista, 7, 8, 8.1, 10 |
 PDF-Creator
|
Windows XP and later |
 PDF-XChange Viewer
|
Windows and Mac OS |
 Adobe Acrobat DC
|
Windows, macOS, Android, iOS |
Primary Functionality
|
STDU Viewer
|
Document viewer supporting multiple file formats including PDF, DjVu, FB2, MOBI, TIFF, TXT with tabbed interface and annotations. |
|
SumatraPDF
|
Lightweight PDF viewer with support for various formats including PDF, ePub, CBR, CBZ with minimalistic interface and night mode. |
|
PDFCreator
|
PDF creation and conversion tool allowing to create PDFs from any Windows program with advanced features like encryption and merging. |
|
FlexiPDF
|
Versatile PDF editor supporting editing, form creation, OCR technology, digital signatures and integration with cloud storage. |
|
FreeCommander XE
|
File management application with dual-panel interface supporting file compression, folder synchronization and advanced search. |
|
Adobe Reader
|
Free software for viewing PDF files across multiple platforms with annotation and search functions. |
|
PDF-XChange Editor
|
Feature-rich PDF editor offering advanced editing tools, digital signature support, OCR and cloud services integration. |
|
NAPS2
|
Free open-source scanning tool with OCR capabilities supporting multiple file formats and customizable settings. |
|
PDF-Creator
|
Batch PDF creation software with conversion optimization features supporting annotations and digital signatures. |
|
PDF-XChange Viewer
|
Free PDF viewer with annotation tools, OCR functionality and support for multimedia elements on Windows and Mac OS. |
|
Adobe Acrobat DC
|
Comprehensive PDF software suite with editing, e-signing, OCR technology and integration extending across multiple platforms. |
Licensing & Cost
|
STDU Viewer
|
Free document viewer without ads or pop-ups. |
|
SumatraPDF
|
Open source and free software under GPLv3 license. |
|
PDFCreator
|
Offers both a free version and paid version with additional features. |
|
FlexiPDF
|
Available as a free trial; full functionality requires purchase. |
|
FreeCommander XE
|
Free for personal and commercial use. |
|
Adobe Reader
|
Free to use with frequent updates; paid Adobe Acrobat Pro provides more features. |
|
PDF-XChange Editor
|
Free version with limited features; paid subscription available for full features. |
|
NAPS2
|
Completely free and open source under GPL v2.0 license. |
|
PDF-Creator
|
Paid software featuring batch mode and advanced features. |
|
PDF-XChange Viewer
|
Free PDF viewer; paid editors available separately. |
|
Adobe Acrobat DC
|
Subscription-based software suite with a free trial; higher cost for full features. |
Choosing the right software isn’t just about features. Size, license type, user ratings, and popularity also matter.
This quick comparison shows how STDU Viewer stacks up against STDU Viewer, SumatraPDF, PDFCreator, FlexiPDF, FreeCommander XE, Adobe Reader, PDF-XChange Editor, NAPS2, PDF-Creator, PDF-XChange Viewer and Adobe Acrobat DC in these key areas—helping you find the best alternative for your needs.
Size
|
STDU Viewer
|
|
|
SumatraPDF
|
4.3MB |
|
PDFCreator
|
42.1MB |
|
FlexiPDF
|
252.4MB |
|
FreeCommander XE
|
|
|
Adobe Reader
|
36.1MB |
|
PDF-XChange Editor
|
377.2MB |
|
NAPS2
|
|
|
PDF-Creator
|
2.3MB |
|
PDF-XChange Viewer
|
15.8MB |
|
Adobe Acrobat DC
|
1.1MB |
License
|
STDU Viewer
|
Freeware |
|
SumatraPDF
|
Commercial |
|
PDFCreator
|
Commercial |
|
FlexiPDF
|
Commercial |
|
FreeCommander XE
|
Freeware |
|
Adobe Reader
|
Freeware |
|
PDF-XChange Editor
|
Commercial |
|
NAPS2
|
Freeware |
|
PDF-Creator
|
Demo |
|
PDF-XChange Viewer
|
Freeware |
|
Adobe Acrobat DC
|
Commercial |