Reference

About the data, precision & limits of validity

Every interpolated row and calculator output on Steam-Tables.com is sourced from one printed reference: the Rogers & Mayhew thermodynamic and transport-property tables. Here is exactly what we use, how we use it, and where the limits are.

primary source edition 5, 1995
Rogers, G.F.C., & Mayhew, Y.R.
Thermodynamic and Transport Properties of Fluids: SI Units, 5th ed. Oxford: Blackwell. ISBN 978-0-631-19703-4.
All tabulated values mirror the printed source verbatim. Interpolation is linear between adjacent rows.

Validity ranges

TableRangePrecisionNotes
Water/steam · sat. temperatureTₛ ∈ [0, 374.15] °C±0.05% on h, s · ±0.01% on PTriple → critical
Water/steam · sat. pressureP ∈ [0.006, 220.9] bar±0.05% on h, sTriple → critical
Superheated steamT ∈ [100, 800] °C, P ∈ [0.01, 1000] bar±0.1%Outside saturation dome
Super-critical steamT ∈ [400, 800] °C, P ∈ [221, 1000] bar±0.2%Above critical point
MercuryT ∈ [0, 600] °C±0.5%Liquid + vapour
Dry air (low p)T ∈ [200, 2200] KIdeal-gas limit
Cp of gases / vapoursT ∈ [200, 2200] K10 species incl. N₂, O₂, CO₂
Molar propertiesT ∈ [200, 2200] Kh̄, ū, s̄°
Interpolation method
For any input value between two tabulated rows, the row is reconstructed using linear interpolation on every column independently. We never extrapolate beyond the tabulated range — a query outside the valid range returns an explicit error, not a silent estimate.
y(x) = y₁ + (x − x₁) · (y₂ − y₁) / (x₂ − x₁)
What this is — and isn't
  • Built for students working through coursework and exam prep.
  • Not a safety-critical tool. Don't use these values for plant design, pressure-vessel sizing, or anywhere a mis-interpolated row would matter.
  • For high-precision work, use the IAPWS-IF97 formulations or your CAS of choice.
Disclaimer
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