Plane angles have been measured in many different units. The most contemporary units are the degree ( ° ) and radian (rad), but many others have been used throughout history.
The radian (rad) is the SI unit for measuring angles. one radian is just under 57.3 degrees. Accepted prefixes still not accepted in pure math.
In-plane geometry, octant is a circular sector obtained by division of the full circle into 8 equal parts, hence the name. It is a sector with a central angle of 45°.
Divide the octant value by 1.273240
radian = octant / 1.273240
Multiply the radian value by 1.273240
octant = radian x 1.273240
One radian (rad) is equal to 1.273240 octant
1 radian (rad) = 1.273240 octant
One octant is equal to 0.785398 radian (rad)
1 octant = 0.785398 radian (rad)