B−V color index to kelvins
Type a value in B−V to get it in K instantly.
3,333.197K
Nothing on our list is smaller: Betelgeuse is 1.08× hotter. Its light peaks at about 869.4 nm.
Convert the other way: K to B−V
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 B−V 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: 1.85 B−V = 3,333.2 K.
Every unit
That star in every measure
Tables
B−V to K conversion table
| B−V | K |
|---|---|
| -0.3 B−V | 16,602.4 K |
| -0.2 B−V | 13,584.8 K |
| -0.1 B−V | 11,572.8 K |
| 0 B−V | 10,125.2 K |
| 0.2 B−V | 8,163.01 K |
| 0.4 B−V | 6,880.24 K |
| 0.6 B−V | 5,967.54 K |
| 0.65 B−V | 5,778.42 K |
| 0.8 B−V | 5,280.67 K |
| 1 B−V | 4,742.74 K |
| 1.2 B−V | 4,308.73 K |
| 1.5 B−V | 3,793.51 K |
| 1.85 B−V | 3,333.2 K |
K to B−V conversion table
| K | B−V |
|---|---|
| 3,330 K | 1.85278 B−V |
| 3,790 K | 1.50233 B−V |
| 4,310 K | 1.19935 B−V |
| 4,740 K | 1.00114 B−V |
| 5,280 K | 0.800223 B−V |
| 5,780 K | 0.649569 B−V |
| 5,970 K | 0.599373 B−V |
| 6,880 K | 0.400045 B−V |
| 8,160 K | 0.200389 B−V |
| 10,100 K | 0.00202886 B−V |
| 11,600 K | -0.101612 B−V |
| 13,600 K | -0.200631 B−V |
| 16,600 K | -0.299936 B−V |
Quick answers
Quick answers
- How many K is 1 B−V?
- 1 B−V is 4,742.74 K.
- How many K is 1.85 B−V?
- 1.85 B−V is 3,333.2 K.
The units
About these units
B−V color index (B−V)
Difference of blue and visual magnitudes.
Kelvins (K)
Surface (effective) temperature.
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