AI-powered estimation via MCP
Open Calc Studio is fully accessible via the Model Context Protocol (MCP). This means AI assistants like Claude can directly create budgets, add items, recalculate and export — without manual input.
- Create and manage budgets from Claude Code or other AI tools
- Automatically extract quantities from IFC/IFCX models
- Look up reference projects for realistic unit prices
- Export to PDF and IFCX directly from the AI workflow
- Extensible via the extension catalog
Tested on real files: FIEBDC-3 (.bc3)
We imported 22 real .bc3 budgets, exported them and imported them again — including the Andalusian cost database BCCA 2023 with 46,215 rows.
- All amounts and chapter totals identical after the round trip (± 0.01)
- 21 of the 22 files identical field by field; in 1 file only a duplicate chapter code gets a suffix
- Every bug found in the importer and exporter fixed; the test runs in the test suite
Why Open Calc Studio?
Cost estimates and budgets are essential for every construction project. Existing estimation software costs thousands of euros per license and locks you into proprietary formats. Open Calc Studio offers a fully open-source alternative that is just as powerful.
With direct connections to STABU/RAW standards, IFCX models for automatic quantities, and AI integration via MCP, Open Calc Studio is built for the future of AEC cost estimation.
Features
STABU/RAW integration
Full support for STABU and RAW standards for standardized specifications and cost estimates according to Dutch norms.
IFCX quantities
Automatically extract quantities from IFCX models. Link budget items directly to model elements for accurate calculations.
MCP Server
Fully accessible via Model Context Protocol. AI assistants can create, edit and export budgets.
Extension system
Extensible via an extension catalog. Add industry-specific calculation methods, templates and integrations.
Chapters & sections
Organize budgets into chapters, sections and budget items. Flexible hierarchy with automatic numbering.
Reference projects
Look up unit prices from reference projects. Build a reusable database of prices and key figures.
PDF & IFCX export
Export budgets as professional PDF reports or as IFCX data for exchange with other tools in the ecosystem.
Overhead costs
Configurable overhead costs: general site costs, profit & risk, CAR insurance and other surcharges automatically calculated.
Recalculation
One-click recalculation of the entire budget. All subtotals, VAT and overhead costs are automatically updated.
39 languages
Full interface translation in 39 languages, including right-to-left for Arabic, Farsi, Hebrew and Urdu. English is the default; pick your language via Preferences → General.
Reports in your own language
Printing and PDF reports follow the separate Report language setting: headings, units and number and date formatting (1.234,56 € in Spanish, € 1,234.56 in English).
High and low VAT
Choose the VAT rate per chapter, item or line. Subtotals and the grand total automatically use the right rate.
FIEBDC-3 (.bc3)
Import and export the Spanish exchange format FIEBDC-3, common across the Spanish construction sector — proven loss-free for amounts and structure.
ÖNORM A 2063 (.onlv)
Read Austrian Leistungsverzeichnisse and Leistungsbücher and export as .onlv, validated against the official XML schemas.
Technology
Built with TypeScript and Rust via Tauri 2. Runs as a desktop application on Windows, macOS and Linux, and as a web application in the browser. Includes MCP Server for AI integration and extension system for customization.
We are looking for testers: users of .bc3 files, Mac users and native speakers for the 39 languages. Get in touch via GitHub issues.