AcroForms vs. XFA: Complete Guide to PDF Forms

Three PDF Form Types. Very Different Behavior.

PDF forms are not a single standard. There are three distinct form types in common use, and they behave differently across viewers, platforms, and standards compliance scenarios. Understanding the differences is not an academic exercise: getting the form type wrong causes real failures, from blank renders in Chrome to rejected PDF/A submissions to migration projects that produce broken output.

This post is the definitive guide to AcroForms, static XFA, and dynamic XFA, covering what each is, how each behaves, and how to choose the right path forward for each type.

AcroForms

AcroForms are the native PDF interactive form standard. They were introduced in PDF 1.2 and have been part of the PDF specification ever since, including PDF 2.0 (ISO 32000-2:2017). AcroForms store form fields, field values, and field appearance properties directly within the PDF document structure using standard PDF marking operators.

Because AcroForms use standard PDF content for rendering, any compliant PDF viewer can render them correctly. They work in Chrome, Firefox, Safari, iOS, Android, and every desktop PDF viewer. They are the only interactive form format permitted in PDF/A-2 and later. They are fully supported in PDF 2.0. For new form development in 2026, AcroForm is the correct choice without qualification.

Static XFA

Static XFA forms use a hybrid architecture. The base page appearance is rendered using standard PDF marking operators (like AcroForms), but the form logic, field definitions, and data binding are described using XFA (XML Forms Architecture) grammar stored in the PDF's XFA stream. The visual rendering depends on the PDF content, so static XFA has broader viewer support than dynamic XFA.

However, static XFA is still an XFA form. It is deprecated in PDF 2.0, not permitted in PDF/A, and may not render correctly outside of Acrobat for complex forms. The fact that it has partial viewer support is a floor, not a ceiling: it will behave consistently in Acrobat and inconsistently everywhere else.

Dynamic XFA

Dynamic XFA forms use XFA exclusively. There is no PDF-based page content. The entire form, including page dimensions, field positions, text flow, and layout, is calculated by the XFA rendering engine at open time using XFA grammar. Nothing about the visual presentation is defined in standard PDF terms.

This makes dynamic XFA the most powerful form type for complex, data-driven documents that need to reflow based on content. It also makes it the most fragile from a compatibility standpoint. Dynamic XFA only renders correctly in environments with a full XFA rendering engine, which in practice means Adobe Acrobat or a tool built on the same engine, such as Forms Extension for Adobe PDF Library.

Dynamic XFA does not render in Chrome. It does not render on mobile. It is not permitted in PDF/A. It is deprecated in PDF 2.0. Organizations with dynamic XFA forms in their active workflows have a migration decision to make.

Compatibility Comparison

XFA Deprecation: The Practical Impact

XFA deprecation in PDF 2.0 does not mean XFA forms stop working in Acrobat today. But it does mean that the broader PDF ecosystem has no obligation to support XFA going forward. Browser vendors, mobile app developers, and PDF tool vendors are under no standards-based requirement to maintain XFA support. The trend line is one-directional: XFA support will narrow over time, not expand.

For organizations with XFA in their document stack, the question is not whether to migrate, but when and in what order.

Processing XFA and AcroForms Programmatically

Forms Extension for Adobe PDF Library provides API-level support for all three form types: AcroForms, static XFA, and dynamic XFA. It handles rendering, flattening, XFA-to-AcroForm conversion, and data import/export for all three types in server environments without Acrobat. Code samples are available in the APDFL GitHub repository.

Frequently Asked Questions

What is the difference between AcroForm and XFA?

AcroForms use standard PDF content for interactive form fields and are part of the PDF specification. XFA is an Adobe-proprietary XML-based form format deprecated in PDF 2.0. AcroForms work everywhere. XFA requires Acrobat or an XFA rendering engine.

Are XFA forms still supported?

XFA forms are still supported in Adobe Acrobat for backward compatibility, but the format is deprecated in PDF 2.0, excluded from PDF/A, and not supported in Chrome, Firefox, or mobile viewers.

What replaced XFA in PDF 2.0?

PDF 2.0 does not include XFA. The supported interactive form format is AcroForm. Organizations migrating from XFA should convert to AcroForm for long-term compatibility.

Which PDF form type should I use in 2026?

Use AcroForm for all new form development. For existing XFA forms, flatten completed forms for archiving and convert interactive forms to AcroForm for continued use.

Learn more about Forms Extension at datalogics.com/pdf-form-functions.

Sign up for a free trial of our Adobe PDF Library Forms Extension SDK and start on your proof of concept today.