zSolver is a desktop application for calculating natural gas compressibility factors using the AGA-8 Detail Characterization Method. Enter your gas composition, pressure, and temperature, and get Z-factors, densities, and thermodynamic properties instantly. Available in English, Spanish, Portuguese, German, and French.
The successor to zCalc, rebuilt from the ground up with a modern interface and the same trusted AGA-8 calculation engine used by pipeline and process engineers worldwide.
**Instant results** — Enter your composition once, then vary pressure and temperature as fast as you can type. Results update immediately. No waiting, no "calculate" button, no batch processing.
**Composition management** — Save and recall gas compositions by name. Build a library of your standard pipeline gases, test mixtures, and customer compositions. Never re-enter the same 21-component mixture twice.
**Sensitivity tables** — Generate Z-factor tables across a range of pressures and temperatures with one click. Export to CSV or copy directly to your spreadsheet.
**Professional reports** — Generate presentation-ready output showing your composition, conditions, and results. Suitable for inclusion in engineering calculations, pipeline design packages, and regulatory filings.
**Multi-language interface** — Available in English, Spanish, Portuguese, German, and French. The interface detects your system language automatically.
**Built for engineers** — Imperial and SI unit systems. Clean, focused interface with no clutter. Designed by an engineer who uses it.
Pipeline engineers calculating compressibility for flow measurement and custody transfer
Process engineers sizing equipment and evaluating gas processing conditions
Measurement technicians verifying flow computer configurations
Gas plant operators validating chromatograph analyses
Consultants who need a reliable, portable AGA-8 tool on their laptop
Anyone upgrading from zCalc
Implements the AGA-8 Detail Characterization Method per AGA Report No. 8 (AGA8-DC92)
Aligned with ISO 12213-2 for international use
Full 21-component characterization: Methane through Argon
Validated against NIST reference values and published AGA-8 verification tables
Temperature range: 263 K to 338 K (-10°C to 65°C / 14°F to 149°F)
Pressure range: 0 to 12 MPa (0 to 1740 psia)
Mole fraction validation with configurable summation tolerance
Supports both Imperial (°F, psia) and SI (°C, MPa) unit systems
Native Windows application — no Java, no .NET runtime, no browser required
Runs on Windows 10 and Windows 11
Lightweight installer, minimal disk footprint