Celsius is a temperature scale based on the freezing and boiling points of water.
Celsius to Romer
Convert celsius (°C) to romer (°Ro) instantly. Free online temperature converter with formulas, tables and examples.
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Romer is a historical temperature scale where water freezes at 7.5° and boils at 60°.
°Ro = (°C × 21/40) + 7.5
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Formula
°Ro = (°C × 21/40) + 7.5
°C = (°Ro × 40/21) − 100/7
Conversion table
| -40.00 °C | -13.50 °Ro |
| -20.00 °C | -3.00 °Ro |
| 0.00 °C | 7.50 °Ro |
| 10.00 °C | 12.75 °Ro |
| 20.00 °C | 18.00 °Ro |
| 25.00 °C | 20.62 °Ro |
| 30.00 °C | 23.25 °Ro |
| 37.00 °C | 26.93 °Ro |
| 100.00 °C | 60.00 °Ro |
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Frequently asked questions
What is the source unit in this conversion?
The source unit is Celsius (°C). Celsius is a temperature scale based on the freezing and boiling points of water.
What is the destination unit in this conversion?
The destination unit is Romer (°Ro). Romer is a historical temperature scale where water freezes at 7.5° and boils at 60°.
How do I convert Celsius to Romer?
Use the formula °Ro = (°C × 21/40) + 7.5. For example, converting a sample value follows the same equation shown in the conversion table above.
Is the Celsius to Romer conversion exact?
Yes. The relationship between the two scales is a fixed linear equation, so the conversion is mathematically exact with no rounding of constants.
Where is this conversion commonly used?
Temperature conversions like this one appear in science, engineering, weather reporting, and historical or regional references that still use Romer.
Can I convert Romer back to Celsius?
Yes. Use the reverse formula °C = (°Ro × 40/21) − 100/7 to convert Romer back to Celsius.
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About this conversion
This page converts Celsius (°C) into Romer (°Ro), two scales used to measure temperature.
Celsius to Romer conversions come up in science, engineering, weather reporting, and historical references, depending on which scale is in use.
The formula is °Ro = (°C × 21/40) + 7.5, a linear equation that accounts for both the scale factor and the zero-point offset between the two scales.
The conversion is exact: it uses fixed constants defined by the relationship between the two scales, not a measured or approximate factor.
Celsius is a temperature scale based on the freezing and boiling points of water. Romer is a historical temperature scale where water freezes at 7.5° and boils at 60°.