A steam table calculator for saturated, superheated and compressed water
This steam table calculator gives the thermodynamic properties of water and steam for any temperature and pressure that industry uses, without paging through printed tables or interpolating between rows. Look up saturated steam by temperature or by pressure, or enter both to get superheated steam, supercritical fluid or compressed liquid. Each answer lists density, specific volume, enthalpy, internal energy, entropy, both heat capacities and the speed of sound.
Every number is calculated from IAPWS-IF97, the Industrial Formulation 1997 published by the International Association for the Properties of Water and Steam (release R7-97(2012)). It is the formulation used for power-plant acceptance tests and boiler design worldwide. Nothing is copied from commercial tables: the equations run in your browser.
Results can be shown in SI units (°C, bar, kJ/kg) as used in India, the UK and Europe, or in US customary units (°F, psia, Btu/lb). Pressure can be typed in bar, MPa, kPa, psia, kgf/cm² or as gauge pressure. The values are for engineering calculations; check critical design work against the release itself.
How to use the steam table calculator
- Choose Saturated by temperature, Saturated by pressure or Superheated or liquid (p, T).
- Type the temperature and/or pressure and pick their units. Gauge units (bar g, psig) add one standard atmosphere for you.
- For wet steam, enter the dryness fraction x to add a mixture column (x = 0.9 means 90% vapour by mass).
- Switch the output between SI and US units, and press Copy results to paste the property table into a report or spreadsheet.
- Under Saturation table, set the first value, last value and step to build your own steam table, then download it as CSV.
Steam Table Calculator features
All IF97 regions
Compressed liquid (region 1), steam (region 2), the near-critical region 3, the saturation line (region 4) and steam up to 2,000 °C (region 5).
Checked against the release
The built-in test reproduces every verification value printed in IAPWS R7-97(2012) to all nine digits.
Superheat or subcooling
In the p, T mode the calculator names the phase and states how far you are above or below the boiling point at that pressure.
Wet steam mixtures
Enter a dryness fraction to get v, h, u and s of the liquid–vapour mixture.
Your own steam table
Up to 200 rows by temperature or pressure, with h_f, h_fg, h_g, s_f and s_g, as a CSV download.
How IAPWS-IF97 calculates steam properties
IF97 splits the range 0–800 °C up to 100 MPa, and 800–2,000 °C up to 50 MPa, into five regions. Regions 1, 2 and 5 are equations for the Gibbs free energy g(p, T); region 3 is an equation for the Helmholtz free energy f(ρ, T); region 4 is the saturation curve. Every property is a derivative of one of these functions. For example, enthalpy in region 1 is h = RT·τ·∂γ/∂τ with γ = g/(RT), τ = 1386 K/T and R = 0.461526 kJ/(kg·K).
The saturation pressure comes from a single quadratic equation that can be solved directly for pressure or for temperature, so the two saturation modes are exactly consistent. Region 3 needs density as an input, so for a given pressure the calculator searches the isotherm for the density that reproduces it, choosing the liquid-like or vapour-like root according to the side of the saturation line you are on.
| State | IF97 result | Notes |
|---|---|---|
| Saturation at 100 °C | p = 1.01418 bar, h_fg = 2,256.47 kJ/kg | Not exactly 1.01325 bar: 100 °C is not the boiling point at 1 atm on the ITS-90 scale |
| Saturation at 10 bar | T = 179.89 °C | Release Table 36: 453.035632 K at 1 MPa |
| 10 bar, 250 °C | Superheated steam, 70.11 °C of superheat | Region 2 |
| 27 °C (300 K), 30 bar | h = 115.331 kJ/kg | Compressed liquid, release Table 5 |
Reading the results correctly
- The reference state is the IAPWS convention: internal energy and entropy of saturated liquid at the triple point (0.01 °C) are zero. Tables that use another reference give different absolute h and s, but the same differences.
- Latent heat h_fg falls to zero at the critical point, 373.946 °C and 220.64 bar, where liquid and vapour become identical.
- Specific volume is the inverse of density: steam at 10 bar occupies about 0.194 m³/kg, roughly 170 times the volume of the saturated water.
- Near the critical point heat capacity and compressibility rise steeply, so small changes in input produce large changes in cp and speed of sound.
- IF97 was fitted to the scientific formulation IAPWS-95. The release gives uncertainty maps for volume, cp, speed of sound and saturation pressure; they grow sharply near the critical point, and above 1,000 °C no definitive estimate is possible.
Related calculators
Convert units with the pressure converter, temperature converter and energy converter (kJ, Btu and kcal), or size a water line with the pipe size calculator.
Steam Table Calculator FAQ
How do I use a steam table calculator by temperature?
Choose Saturated by temperature and enter the temperature. The calculator returns the saturation pressure and the liquid, evaporation and vapour columns, including the latent heat h_fg. It works from 0 °C to the critical point, 373.946 °C.
How do I find superheated steam properties?
Choose Superheated or liquid (p, T) and enter both the pressure and the temperature. If the temperature is above the boiling point at that pressure the state is superheated steam, and the result shows how many degrees of superheat it has.
What is the saturation temperature of steam at 10 bar?
About 179.89 °C (453.04 K) at 10 bar absolute. If your gauge reads 10 bar, select bar (gauge): the absolute pressure is 11.01 bar and the saturation temperature is about 184.1 °C.
Which steam table does this use?
IAPWS-IF97, the Industrial Formulation 1997 for the Thermodynamic Properties of Water and Steam, in its 2012 revised release (R7-97(2012)). Its verification tables are reproduced exactly by the calculator’s built-in test.
What is the dryness fraction?
The mass fraction of vapour in wet steam. Mixture properties are interpolated between the saturated liquid and vapour values: h = h_f + x·h_fg, and the same for v, u and s.
Why does my old steam table give slightly different numbers?
Older tables are based on IFC-67 or use a different reference state or temperature scale. Differences of a few tenths of a kJ/kg are normal; differences in absolute enthalpy of tens of kJ/kg usually mean a different reference point.