Romer is a historical temperature scale where water freezes at 7.5° and boils at 60°.
Romer to Celsius
Convert romer (°Ro) to celsius (°C) instantly. Free online temperature converter with formulas, tables and examples.
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Celsius is a temperature scale based on the freezing and boiling points of water.
°C = (°Ro × 40/21) − 100/7
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Formula
°C = (°Ro × 40/21) − 100/7
°Ro = (°C × 21/40) + 7.5
Conversion table
| -13.50 °Ro | -40.00 °C |
| -3.00 °Ro | -20.00 °C |
| 7.50 °Ro | 0.00 °C |
| 12.75 °Ro | 10.00 °C |
| 18.00 °Ro | 20.00 °C |
| 20.62 °Ro | 25.00 °C |
| 23.25 °Ro | 30.00 °C |
| 26.93 °Ro | 37.00 °C |
| 60.00 °Ro | 100.00 °C |
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Frequently asked questions
What is the source unit in this conversion?
The source unit is Romer (°Ro). Romer is a historical temperature scale where water freezes at 7.5° and boils at 60°.
What is the destination unit in this conversion?
The destination unit is Celsius (°C). Celsius is a temperature scale based on the freezing and boiling points of water.
How do I convert Romer to Celsius?
Use the formula °C = (°Ro × 40/21) − 100/7. For example, converting a sample value follows the same equation shown in the conversion table above.
Is the Romer to Celsius 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 Celsius.
Can I convert Celsius back to Romer?
Yes. Use the reverse formula °Ro = (°C × 21/40) + 7.5 to convert Celsius back to Romer.
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About this conversion
This page converts Romer (°Ro) into Celsius (°C), two scales used to measure temperature.
Romer to Celsius conversions come up in science, engineering, weather reporting, and historical references, depending on which scale is in use.
The formula is °C = (°Ro × 40/21) − 100/7, 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.
Romer is a historical temperature scale where water freezes at 7.5° and boils at 60°. Celsius is a temperature scale based on the freezing and boiling points of water.