Form.io
Enterprise form builder and API platform for developers
About Form.io
Form.io is a self-hosted enterprise form building and data management platform that enables developers to create complex forms with a drag-and-drop builder while automatically generating REST APIs. It supports offline mode, fillable PDF forms, conditional logic, validations, and workflow capabilities. Delivered as Docker containers, Form.io deploys into customer on-premise or private cloud environments with full data sovereignty.
Pros & Cons
Pros
- Full self-hosting with complete data sovereignty
- Automatic API generation from form definitions
- Enterprise-grade security with field-level encryption
- Supports offline mode for field workers
- Highly customizable with embeddable form builder
Cons
- No transparent public pricing — requires sales contact
- Complex setup process for self-hosted deployments
- Steep learning curve for advanced configurations
- Enterprise-focused — not ideal for small projects
Key Features
Drag-and-drop form builder
Drag-and-drop form builder
Automatic REST API generation
Automatic REST API generation
Offline mode support
Offline mode support
Fillable PDF forms and
Fillable PDF forms and PDF export
Complex conditional logic and validations
Complex conditional logic and validations
Workflow and approval capabilities
Workflow and approval capabilities
Self-hosted Docker container deployment
Self-hosted Docker container deployment
Field-level encryption and audit logging
Field-level encryption and audit logging
SDK generation for multiple languages
SDK generation for multiple languages
Application internationalization
Application internationalization
Pricing
- Unlimited forms & resources
- Self-hosted Docker containers
- PDF server support
- Advanced audit logging
- Field-level encryption
Featured In
7 Best Open-Source Form Builders for Developers (2026)
Best for enterprise development teams building complex form-driven business applications that need automatic API generation, offline support, and strict compliance capabilities.
Best Form Builders for File Upload Handling (2026)
Best for developer teams that need uploaded files to land in their own storage under their own security rules.