How many arcseconds are in a degree?

There are 3,600 arcseconds in one degree. This comes from a degree being divided into 60 arcminutes, and each arcminute being divided into 60 arcseconds (60 x 60 = 3,600). Arcseconds are used in astronomy, surveying, GPS coordinates and navigation wherever very precise angular measurement is needed, such as stating a star's position or a survey bearing.

What is the difference between arcseconds and seconds of time?

Arcseconds measure angle (1 degree = 3,600 arcseconds), while seconds of time measure how long it takes Earth to rotate through that angle. Because Earth rotates 360 degrees in 24 hours, 1 degree of rotation equals 240 seconds of time (24 hours x 3,600 seconds / 360 degrees). Seconds of time are used in astronomy and longitude calculations to relate angular position to the time of day.

How do I convert degrees, minutes and seconds to just seconds?

First convert the whole angle to decimal degrees: decimal degrees = degrees + minutes/60 + seconds/3600. Then multiply the decimal degrees by 3,600 to get the total in arcseconds. For example, 10 degrees 30 minutes 15 seconds equals 10.5042 decimal degrees, which equals 37,815 arcseconds.

Degrees to Seconds Converter

Convert an angle in degrees into arcseconds, the standard unit of angular precision used in astronomy, surveying, navigation and GPS coordinates. One degree equals 3,600 arcseconds.

This tool also converts your angle into seconds of time (used for longitude and Earth rotation calculations), and shows the full degrees, minutes, seconds breakdown.

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Verified 2026 Standard sexagesimal angle units (1 degree = 60 arcminutes = 3,600 arcseconds).

1. Enter Your Angle

Input format

Angle (decimal degrees)

Degrees, minutes, seconds

2. About This Conversion

Arcseconds measure angle: 1 degree = 60 arcminutes = 3,600 arcseconds. This is the unit used for star positions, survey bearings and coordinate precision.

Seconds of time relate angle to Earth's rotation: since Earth turns 360 degrees in 24 hours, 1 degree = 240 seconds of time. This is used for longitude and solar time calculations.

Conversion Results

Decimal Degrees

Your angle in degrees

Arcseconds
-
Total angular seconds

Arcminutes

Total angular minutes

Seconds of Time

Earth rotation equivalent

Full Breakdown

Decimal degrees-

Degrees, minutes, seconds (DMS)-

Total arcminutes-

Total arcseconds-

Time Equivalent

Seconds of time (1 deg = 240 sec)-

Minutes of time-

Hours of time-

H:M:S of time-

Result: Enter an angle above.

How to Convert Degrees to Seconds

An angle in degrees can be split into smaller sexagesimal units the same way an hour splits into minutes and seconds. One degree equals 60 arcminutes, and one arcminute equals 60 arcseconds, so one degree equals 3,600 arcseconds in total. To convert decimal degrees to arcseconds, multiply the decimal degree value by 3,600. For example, 10.5 degrees x 3,600 = 37,800 arcseconds.

Converting Degrees, Minutes, Seconds to Total Seconds

If your angle is already expressed in degrees, minutes and seconds (DMS), first convert it to decimal degrees using the formula: decimal degrees = degrees + (minutes / 60) + (seconds / 3600). Then multiply the result by 3,600 to get the total arcseconds. For example, 10 degrees 30 minutes 0 seconds converts to 10.5 decimal degrees, which equals 37,800 arcseconds.

Arcseconds vs Seconds of Time

It is easy to confuse two different meanings of "seconds" when dealing with degrees. Arcseconds are a unit of angle (3,600 per degree), used in astronomy, surveying and GPS coordinates to express angular precision. Seconds of time are a unit of duration related to Earth's rotation. Because Earth completes a full 360 degree rotation in 24 hours, each degree of rotation corresponds to 240 seconds of time (24 hours x 3,600 seconds per hour, divided by 360 degrees). Astronomers use seconds of time when converting between right ascension (measured in hours, minutes, seconds of time) and celestial longitude (measured in degrees).

Unit	Conversion	Common Use
1 degree	60 arcminutes	Base angle unit
1 degree	3,600 arcseconds	Astronomy, surveying, GPS precision
1 arcminute	60 arcseconds	Navigation, map coordinates
1 degree	240 seconds of time	Longitude, right ascension conversion
15 degrees	1 hour of time	Time zones (360 deg / 24 hr)

Why Arcseconds Matter for Precision

A single arcsecond is a very small angle: 1/3600th of a degree. At the distance of the Moon, one arcsecond corresponds to roughly 1.9 km. GPS coordinates are often expressed to a fraction of an arcsecond to pinpoint a location to within a few centimetres. Surveyors use arcseconds when recording bearings and boundary angles because degrees and even arcminutes are not precise enough for legal land descriptions. Astronomers use arcseconds to measure the apparent size and separation of objects in the sky, since most celestial objects appear only a few arcseconds to a few degrees across.

Worked Example

Take an angle of 10.5 decimal degrees. Multiplying by 3,600 gives 37,800 arcseconds. Expressed as degrees, minutes, seconds this is 10 degrees, 30 minutes, 0 seconds (since 0.5 degrees = 30 arcminutes exactly). Converting to seconds of time, 10.5 degrees x 240 = 2,520 seconds of time, which is 42 minutes 0 seconds, or 0 hours 42 minutes 0 seconds.

Related Angle Converters

Angle Conversion Calculator: convert between degrees, radians, gradians and more.
Degrees Minutes Seconds Calculator: work with DMS angle notation directly.
Decimal Degrees to DMS Converter: the reverse conversion, decimal to DMS.
DMS to Decimal Degrees Converter: convert DMS notation back to decimal degrees.
Degrees to Radians Calculator: convert degrees to the radian angle unit used in calculus and physics.

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Sources: Standard sexagesimal angle unit definitions (1 degree = 60 arcminutes = 3,600 arcseconds), as used by the International Astronomical Union and national mapping agencies including Land Information New Zealand (linz.govt.nz) for survey coordinate precision.

This calculator performs a standard mathematical unit conversion and is accurate for any valid angle input. It does not account for angle normalisation (wrapping values above 360 degrees or below 0 degrees) unless you enter a pre-normalised value.