Free Main-Sequence Lifetime Calculator
Estimate how long a star spends on the main sequence: t = t_sun * (M/M_sun) / (L/L_sun), approximated as t ≈ 10^10 * (M/M_sun)^(-2.5) years.
M_sun
Main-Sequence Lifetime
10,000,000,000 yr
Lifetime (Gyr)10.0000 Gyr
Main-Sequence Lifetime vs Stellar Mass
Main-Sequence Lifetime
More massive stars burn through their hydrogen fuel much faster because luminosity rises steeply with mass.
Approximate Formula
t ≈ 10¹⁰ × (M/M_sun)^(-2.5) years
This comes from t ∝ M/L and the mass-luminosity relation L ∝ M^3.5 for main-sequence stars.
Example Calculation
A star with 2 solar masses.
- 01t = 10^10 × 2^(-2.5)
- 022^(-2.5) = 1/√(2^5) = 1/√32 = 0.1768
- 03t = 10^10 × 0.1768 ≈ 1.77 Gyr
- 04About 1.77 billion years on the main sequence.