How to use the relative air mass calculator
Find the path length of sunlight through the atmosphere from the solar zenith angle. Enter solar zenith angle in the field above; the relative air mass, direct sunlight reduction (approx.) are computed instantly and plotted on the chart so you can see how the answer changes.
Common searches this calculator answers include “air mass calculator”, “sunlight path through atmosphere”, “solar zenith air mass”, “calculate relative air mass”, “find relative air mass”.
Formula
Variables
- z — Solar zenith angle (°)
Worked example
With solar zenith angle = 30 °, the calculator gives relative air mass ≈ 1.154701; direct sunlight reduction (approx.) ≈ 33.75782 %.
Frequently asked questions
What is the relative air mass calculator used for?
Find the path length of sunlight through the atmosphere from the solar zenith angle. It helps with questions such as “air mass calculator”, “sunlight path through atmosphere”, “solar zenith air mass”.
What is the formula for the relative air mass calculation?
Relative air mass = 1 / cos(z). Direct sunlight reduction (approx.) (%) = 100 × (1-0.7^[Relative air mass]). Here z is solar zenith angle (°).
What inputs do I need for the relative air mass calculator?
You need solar zenith angle in °. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use the relative air mass calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the relative air mass result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.