Temperature · Unit Converter

Convert Triple Point of Water to Celsius

Convert triple points of water to degrees celsius instantly. °C = (TPW × 273.16) − 273.15 — use the live calculator, the exact formula, a reference-temperature table and worked examples. Also check the Celsius to Triple Point of Water converter for the reverse conversion.

Written by Sunith Babu L, Ph.D., Lead Engineer Reviewed by Girish V Kulkarni Ph.D.
Temperature category 2 min read Published Last reviewed Updated

Units explained

Scientific & Fixed-Point

Triple Point of Water

What is the triple point of water?

The triple point of water is the unique state at which ice, liquid water, and water vapor coexist in equilibrium — exactly 273.16 K (0.01 °C). Treated as a converter unit, 1 triple point of water equals exactly 273.16 kelvins.

Origin of the triple point of water

Adopted as thermometry's master fixed point because it is exactly reproducible in a sealed glass cell, unlike freezing and boiling points, which shift with atmospheric pressure and dissolved impurities.

Where it is used

Calibration laboratories and the International Temperature Scale of 1990 (ITS-90); from 1954 to 2019 the kelvin itself was defined as exactly 1/273.16 of this temperature.

When and where it was developed

Fixed at exactly 273.16 K by the 10th CGPM in 1954; it remained the kelvin's defining point until the 2019 SI redefinition through the Boltzmann constant.

Modern Standard Scales

Celsius

What is a degree celsius?

The degree Celsius (°C) is the SI's everyday temperature unit. One degree Celsius is exactly the same size as one kelvin, with the zero point shifted so that 0 °C = 273.15 K. Water freezes near 0 °C and boils near 100 °C at standard atmospheric pressure.

Origin of the degree celsius

Named for Swedish astronomer Anders Celsius, who in 1742 proposed a 100-degree scale between the boiling and freezing points of water. His original scale ran in reverse (0 at boiling, 100 at freezing); it was inverted to the modern direction shortly after his death.

Where it is used

The world's standard everyday temperature scale, used in nearly every country — including throughout India — for weather forecasts, cooking, medicine, science classrooms, and industry.

When and where it was developed

Devised by Anders Celsius at Uppsala University, Sweden, in 1742; the inverted modern form was in use by 1745, and the name 'degree Celsius' replaced 'degree centigrade' internationally at the 9th CGPM in 1948.

Triple Point of Water to Celsius conversion formula

The exact relationship between triple points of water and degrees celsius:

°C = (TPW × 273.16) − 273.15
TPW = (°C + 273.15) × 0.003660858105

To convert triple points of water to degrees celsius, multiply the value by 273.16, then subtract 273.15. To reverse, add 273.15 to the value, then multiply by 0.003660858105.

Reference anchors: water freezes at 0.9999633914 TPW = 0 °C and boils at 1.3660492019 TPW = 100 °C (at standard atmospheric pressure).

How to use this converter

Type a value into the calculator. The result in degrees celsius updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Celsius to Triple Point of Water converter for the reverse direction.

Step-by-step: convert triple points of water to degrees celsius

  1. Write down the temperature in triple points of water (TPW).
  2. Multiply the value by 273.16, then subtract 273.15.
  3. The result is the same temperature expressed in degrees celsius (°C).
  4. To reverse, add 273.15 to the value, then multiply by 0.003660858105 — or open the Celsius to Triple Point of Water converter.

Worked examples

Example 1 — Convert 1 TPW to °C:
(1 × 273.16) − 273.15 = 0.01 °C

Example 2 — Convert 100 TPW to °C:
(100 × 273.16) − 273.15 = 27042.85 °C

Triple Point of Water to Celsius conversion table

Physically meaningful reference temperatures, from absolute zero to the surface of the Sun, converted from triple points of water to degrees celsius:

Triple Point of Water [TPW]Celsius [°C]Reference point
0-273.15Absolute zero
0.8535290672-40Where Celsius and Fahrenheit coincide (−40°)
0.9348814695-17.7777777778Zero Fahrenheit (0 °F)
0.99996339140Water freezes (0 °C / 32 °F)
10.01Triple point of water
1.036571972510Cool day (10 °C / 50 °F)
1.073180553520Room temperature (20 °C / 68 °F)
1.09148484425Standard laboratory temperature (25 °C)
1.109789134630Hot day (30 °C / 86 °F)
1.135415141337Human body temperature (37 °C / 98.6 °F)
1.146397715640Heat-wave day (40 °C / 104 °F)
1.183006296750Hot tap water (50 °C / 122 °F)
1.3660492019100Water boils (100 °C / 212 °F)
1.6589178503180Moderate baking oven (180 °C / 356 °F)
21.15243813155504.85Surface of the Sun (≈5,505 °C)

Frequently asked questions

What is 1 TPW in °C?
1 TPW equals 0.01 °C — normal human body temperature.
How do I convert triple points of water to degrees celsius?
Use the formula °C = (TPW × 273.16) − 273.15: multiply the value by 273.16, then subtract 273.15.
How do I convert degrees celsius back to triple points of water?
Apply the reverse formula TPW = (°C + 273.15) × 0.003660858105 — add 273.15 to the value, then multiply by 0.003660858105 — or use the Celsius to Triple Point of Water converter.
At what temperature do the Triple Point of Water and Celsius scales read the same number?
Both scales show the same number at 1.0036375661: 1.0036375661 TPW = 1.0036375661 °C. Set °C = TPW in the conversion formula and solve to verify it.
Can a temperature be below absolute zero?
No. Absolute zero (0 K = −273.15 °C = −459.67 °F) is the floor of the thermodynamic temperature scale. The calculator flags any input that would fall below it.

Convert Triple Point of Water to other temperature units

Show all Triple Point of Water conversions

Sources & references

Conversion relationship (°C = (TPW × 273.16) − 273.15) verified against the following authoritative sources:

Results are provided for general reference. Verify critical measurements against an authoritative standard.