OST Visualizer
Open your On-Screen Takeoff projects and review them in 2D plan view. Upgrade to visualize in 3D, edit conditions, and export to DXF, PDF, and OBJ.
Source-available under Elastic License 2.0
Latest: v1.2.6.1 · Windows
Features
Everything you need for 3D takeoff review
Built for construction estimators who work with On-Screen Takeoff daily.
2D Plan View
Interactive view with annotations overlaid on project pages.
PDF Plan Sheets
View PDF drawings at any scale.
Multi-Database
Open and browse multiple project files at the same time.
Bid Organization
Full project hierarchy for navigating bids and conditions.
3D VisualizationCommercial
See takeoff geometry rendered in full 3D with transparent overlays.
Import / ExportCommercial
Move data between OST, OSP, PDF, DXF, OBJ, and FBX formats.
Condition ManagementCommercial
Create, edit, duplicate, and organize conditions across bids.
Realtime Sync (free companion tool)
Detects when On-Screen Takeoff is active and picks up changes automatically.
Licensing
Free vs. Commercial License
OST Visualizer is source-available under the Elastic License 2.0. A commercial license unlocks all features for production use.
| Feature | Free (Viewer) | Commercial License |
|---|---|---|
| Open and browse projects | ✓ | ✓ |
| 2D plan view (read-only) | ✓ | ✓ |
| 3D visualization | — | ✓ |
| Edit takeoffs, conditions, bids | — | ✓ |
| Import/Export (PDF, DXF, OBJ, FBX) | — | ✓ |
| Production use | — | ✓ |
| Support | Community | Email (fabian@fabianhad.com) |
| Price | Free | Get a license |
License Terms
Elastic License 2.0
OST Visualizer is source-available. Here's what the license allows.
What you can do
- View source code — read, study, and learn from the codebase
- Contribute — submit pull requests and improvements
- Non-production use — run the software for development, testing, and personal evaluation
- Production use with a license — use all features in commercial environments with a valid license key
What you cannot do
- Circumvent the license key — you may not disable, remove, or bypass license key functionality
- Offer as a hosted service — you may not provide the software to third parties as a managed service
- Remove notices — you may not alter or remove licensing or copyright notices
Who it's for
Built for construction professionals
Estimators
Reviewing On-Screen Takeoff projects visually before bidding.
Project Managers
Inspecting bid scope across multiple databases.
Construction Teams
Working with takeoff data in 2D and 3D.
Technology
Built for performance
Native desktop application with hardware-accelerated 3D rendering.
Performance-critical rendering in C++ with nanobind Python bindings. Qt-based UI. View on GitHub for full details.
Questions about licensing? Contact us