Janskys to AB magnitude
Type a value in Jy to get it in AB mag instantly.
25AB mag
That's 100× as bright as the faintest galaxies in Hubble’s deep fields, while the faintest star the eye can see is 39,821,684× brighter.
Convert the other way: AB mag to Jy
What it means
How bright is that source?
AB magnitudes are defined per unit frequency. Vega-system magnitudes differ by a band-dependent offset; references are rough visual values.
The math
How to convert Jy to AB mag
AB = −2.5 log₁₀(F ÷ 3,631 Jy); F = 3,631 Jy × 10^(−0.4 AB). 1 Jy = 10⁻²⁶ W m⁻² Hz⁻¹.
Example: 3.63×10⁻⁷ Jy = 25.0003 AB mag.
Every unit
That flux density in every unit
Tables
Jy to AB mag conversion table
| Jy | AB mag |
|---|---|
| 3.63×10⁻⁹ Jy | 30.0003 AB mag |
| 2.29×10⁻⁸ Jy | 28.0005 AB mag |
| 3.63×10⁻⁷ Jy | 25.0003 AB mag |
| 3.63×10⁻⁶ Jy | 22.5003 AB mag |
| 3.63×10⁻⁵ Jy | 20.0003 AB mag |
| 0.001 Jy | 16.4001 AB mag |
| 0.00363 Jy | 15.0003 AB mag |
| 0.363 Jy | 10.0003 AB mag |
| 36.3 Jy | 5.0003 AB mag |
| 3,630 Jy | 0.00029906 AB mag |
| 363,000 Jy | -4.9997 AB mag |
AB mag to Jy conversion table
| AB mag | Jy |
|---|---|
| -5 AB mag | 363,100 Jy |
| 0 AB mag | 3,631 Jy |
| 5 AB mag | 36.31 Jy |
| 10 AB mag | 0.3631 Jy |
| 15 AB mag | 0.003631 Jy |
| 16.4 AB mag | 0.00100006 Jy |
| 20 AB mag | 3.631×10⁻⁵ Jy |
| 22.5 AB mag | 3.631×10⁻⁶ Jy |
| 25 AB mag | 3.631×10⁻⁷ Jy |
| 28 AB mag | 2.291×10⁻⁸ Jy |
| 30 AB mag | 3.631×10⁻⁹ Jy |
Quick answers
Quick answers
- How many AB mag is 1 Jy?
- 1 Jy is 8.90007 AB mag.
- How many AB mag is 10 Jy?
- 10 Jy is 6.40007 AB mag.
- How many AB mag is 3.63×10⁻⁷ Jy?
- 3.63×10⁻⁷ Jy is 25.0003 AB mag.
The units
About these units
Janskys (Jy)
10⁻²⁶ W m⁻² Hz⁻¹.
AB magnitude (AB mag)
Astronomical magnitude per unit frequency: 0 is 3,631 Jy.
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