Peak wavelength to kelvins
Type a value in nm to get it in K instantly.
3,334.605K
Nothing on our list is smaller: Betelgeuse is 1.08× hotter. Its light peaks at about 869 nm.
Convert the other way: K to nm
What it means
How hot is that star?
Ballesteros (2012) blackbody fit, for B−V from −0.4 to 2.5; real stars deviate by a few percent, and dust reddening makes stars look cooler.
The math
How to convert nm to K
T = 4600 × (1 ÷ (0.92 BV + 1.7) + 1 ÷ (0.92 BV + 0.62)) K; peak wavelength = 2,897,772 nm·K ÷ T.
Example: 869 nm = 3,334.61 K.
Every unit
That star in every measure
Tables
nm to K conversion table
| nm | K |
|---|---|
| 175 nm | 16,558.7 K |
| 213 nm | 13,604.6 K |
| 250 nm | 11,591.1 K |
| 286 nm | 10,132.1 K |
| 355 nm | 8,162.74 K |
| 421 nm | 6,883.07 K |
| 486 nm | 5,962.49 K |
| 501 nm | 5,783.98 K |
| 549 nm | 5,278.27 K |
| 611 nm | 4,742.67 K |
| 673 nm | 4,305.75 K |
| 764 nm | 3,792.9 K |
| 869 nm | 3,334.61 K |
K to nm conversion table
| K | nm |
|---|---|
| 3,330 K | 870.202 nm |
| 3,790 K | 764.584 nm |
| 4,310 K | 672.337 nm |
| 4,740 K | 611.344 nm |
| 5,280 K | 548.82 nm |
| 5,780 K | 501.345 nm |
| 5,970 K | 485.389 nm |
| 6,880 K | 421.188 nm |
| 8,160 K | 355.119 nm |
| 10,100 K | 286.908 nm |
| 11,600 K | 249.808 nm |
| 13,600 K | 213.071 nm |
| 16,600 K | 174.565 nm |
Quick answers
Quick answers
- How many K is 1 nm?
- 1 nm is 2,897,770 K.
- How many K is 10 nm?
- 10 nm is 289,777 K.
- How many K is 869 nm?
- 869 nm is 3,334.61 K.
The units
About these units
Peak wavelength (nm)
Where its light is brightest (Wien’s law).
Kelvins (K)
Surface (effective) temperature.
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