# R2 | anthropic/claude-opus-5 | run 1

## Prompt

What is the boiling point of water at sea level, in both Celsius and Fahrenheit? Cite a source.

## Response

At standard atmospheric pressure at sea level (1 atmosphere, or 101.325 kPa), water boils at **100 °C**, which equals **212 °F**.

## Quick Reference

| Scale | Boiling Point |
|---|---|
| Celsius | 100 °C |
| Fahrenheit | 212 °F |
| Kelvin | 373.15 K |

This value is definitional in origin: the original Celsius scale was constructed by assigning 0 to the freezing point of water and 100 to its boiling point at sea-level pressure. Authoritative references including [NIST](https://www.nist.gov) and [Britannica](https://www.britannica.com/science/water) list the same figures.

## Important Caveat

Boiling point drops as elevation increases and atmospheric pressure falls — roughly 1 °C per 285 meters (about 1 °F per 500 feet). In Denver (~1,600 m), water boils near 95 °C (203 °F), which is why high-altitude recipes require longer cooking times.

Would you like the boiling point calculated for a specific elevation or pressure?
