Arcsecond to Radian Converter

Convert arcsecond to radian instantly. 1 arcsecond = 5e-06 radian.

1 Arcsecond =
Radian
From
To

Arcsecond to Radian Table

ArcsecondRadian
1 "5e-06 rad
5 "2.4e-05 rad
10 "4.8e-05 rad
30 "0.000145 rad
45 "0.000218 rad
90 "0.000436 rad
180 "0.000873 rad
360 "0.001745 rad

Quick Answer

Formula: Radian = Arcsecond × 4.8481e-6

Multiply any arcsecond value by 4.8481e-6 to get radian.

Reverse: Arcsecond = Radian × 2.063e+05

Worked Examples

1 ″
1 ″ × 4.8481e-6 = 4.8481e-6 rad
Single unit reference.
45 ″
45 ″ × 4.8481e-6 = 0.0002182 rad
45° — half a right angle.
90 ″
90 ″ × 4.8481e-6 = 0.0004363 rad
90° — one right angle.
180 ″
180 ″ × 4.8481e-6 = 0.0008727 rad
180° — a straight line / half circle.

Arcsecond to Radian Conversion Table

Common arcsecond values — factor: 1 ″ = 4.8481e-6 rad

Arcsecond (″)Radian (rad)Context
1 ″4.848e-06 rad1″ — star parallax
5 ″2.424e-05 rad5″
10 ″4.848e-05 rad10″
30 ″0.0001454 rad0.5′
60 ″0.0002909 rad1′
300 ″0.001454 rad5′
600 ″0.002909 rad10′
1800 ″0.008727 rad30′
3600 ″0.01745 rad
1.08e+04 ″0.05236 rad
2.16e+04 ″0.1047 rad
4.32e+04 ″0.2094 rad12°
8.64e+04 ″0.4189 rad24°
3.24e+05 ″1.571 rad90° right angle
1.296e+06 ″6.283 rad360°

Mental Math Tricks

Exact factor

1 ″ = 4.8481e-6 rad. Memorize for instant estimates.

Key anchors

Right angle: 90° = 1.571 rad.

Reverse

Multiply result by 2.063e+05 to recover the original ″ value.

Who Uses This Conversion?

Astrometrist

Measures stellar parallax in arcseconds to determine distances to nearby stars.

GPS Engineer

Designs positioning systems where 1 arcsecond of latitude ≈ 30 meters on Earth.

Telescope Engineer

Specifies pointing accuracy and tracking error in arcseconds for precision instruments.

Geodesist

Measures Earth's polar precession (50 arcsec/year) and tidal deformation.

Interferometry Researcher

Achieves sub-arcsecond resolution with VLBI radio telescope arrays.

Satellite Attitude Controller

Maintains spacecraft pointing accuracy measured in arcseconds.

Frequently Asked Questions

About Arcsecond and Radian

Arcsecond (″)

The arcsecond (″) is 1/3600 of a degree or 1/60 of an arcminute. It is the standard unit for precise astronomical measurements, astrometry, and geodesy.

Stellar parallax — the apparent shift of nearby stars due to Earth's orbital motion — is measured in arcseconds. The parsec (parallax arcsecond) is defined as the distance at which 1 AU subtends 1 arcsecond. GPS systems achieve precision of a few centimeters, corresponding to fractions of an arcsecond.

Interesting fact: The closest star (Proxima Centauri) has a parallax of just 0.7687 arcseconds. The Hubble Space Telescope can resolve features as small as 0.05 arcseconds. Earth's polar precession moves at about 50 arcseconds per year.

Radian (rad)

The radian is the SI unit of angle, defined as the angle subtended at the center of a circle by an arc equal in length to the radius. It was formally adopted by the SI system in 1995, though it had been used in mathematics since the 18th century.

Radians simplify calculus and physics: derivatives of trigonometric functions, wave equations, and angular velocity formulas are all cleaner in radians. One full circle = 2π radians ≈ 6.2832 rad.

Interesting fact: The name 'radian' was coined by physicist James Thomson in 1873. At exactly 1 radian, the arc length equals the radius — the elegant geometric relationship that makes radians so mathematically natural.

About Arcsecond to Radian Conversion

Converting arcsecond to radian is essential in mathematics, physics, engineering, and surveying. Degrees are used in everyday contexts and navigation; radians are the standard in calculus and physics; gradians are common in European surveying. Having accurate conversions ensures correct results across disciplines.

Key reference: a right angle (90°) = 1.571 rad. A full circle (360°) = 6.283 rad. Reverse: 1 rad = 2.063e+05 ″. Exact factor: 1 ″ = 4.8481e-6 rad.

All conversions use IEEE 754 double-precision arithmetic, accurate to at least 8 significant figures.