Delisle is a historical temperature scale.
Delisles to Romers Converter — De to Ro
Convert Delisle (De) to Romer (Ro) using the exact temperature formula. See the formula, worked examples, and conversion table.
Delisles to Romers converter
Converter
Temperature Converter
Convert Celsius, Fahrenheit, Kelvin, Rankine, Delisle, Newton, Reaumur, and Romer.
Context values
Some unit families need one extra value for a physically accurate result.
Romer is a historical temperature scale.
Convert the source temperature to Kelvin, then convert Kelvin to the target scale.
Temperature conversion uses Kelvin as the intermediate absolute scale.
Reserved above the conversion cards and below the converter.
About Converting Delisles to Romers
Delisle and Romer are both historical temperature scales no longer in everyday use — this conversion is mainly useful for historical reference or comparing older scientific texts against each other.
Formula
Convert the source temperature to Kelvin, then convert Kelvin to the target scale.
Both scales are converted through Kelvin as a common absolute reference point.
Simple example
(0 − 32) × 5/9 = 60 °C
0 delisles = 60 romers.
Real-world example
(0 − 32) × 5/9 = 60 °C
0 delisles = 60 romers.
Conversion table
| Delisle (De) | Romer (Ro) |
|---|---|
| -40 De | 74 Ro |
| -20 De | 67 Ro |
| 0 De | 60 Ro |
| 20 De | 53 Ro |
| 37 De | 47.05 Ro |
| 100 De | 25 Ro |
Reverse conversion: Romer to Delisle
(59.65 − 32) × 5/9 = 1 °C
59.65 romers = 1 delisles.
Convert the source temperature to Kelvin, then convert Kelvin to the target scale.
For a page dedicated to this direction, see Romer to Delisle.
Understanding the Delisle (De)
Delisle is a historical temperature scale.
Understanding the Romer (Ro)
Romer is a historical temperature scale.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many romers are in 1 delisle?
1 delisle equals 59.65 romers, using the offset temperature formula rather than an estimate.
How do I convert delisle to romer?
Use the formula shown above: it involves both a multiplication and an addition/subtraction because the two scales don't share a common zero point.
How do I convert romer back to delisle?
Use the reverse factor: 1 romer equals 168.5714286 delisles. You can also use the swap control in the converter above to flip the direction instantly.
What is a delisle?
Delisle (De) is a unit of temperature.
What is a romer?
Romer (Ro) is a unit of temperature.
Is the Delisle to Romer conversion exact?
Yes. Both scales are formally defined relative to the Kelvin scale, so the conversion formula is exact — the only rounding involved is in how many decimal places you choose to display.