How to convert Arcseconds to radians
rad = ″ × π ÷ 648000
One full turn is 2π radians or 360 degrees. Keeping π in the formula avoids rounding a decimal conversion factor before calculating the result.
Worked examples
1 ″ ≈ 0.000004848136811 rad
(1) × π ÷ 648000 ≈ 0.000004848136811
3600 ″ ≈ 0.01745329252 rad
(3600) × π ÷ 648000 ≈ 0.01745329252
Frequently asked questions
Why does the formula include π?
A complete turn is 2π radians, equal to 360 degrees or 400 gradians. Keeping π symbolic avoids prematurely rounding the conversion coefficient.