Reflex angle

342 Degree Angle

19π/10 ≈ 5.969026 radians · 19/20 (95%) of a circle

Diagram of a 342 degree angle342°
Reflex angle: 342°

Key facts

342°

Angle type
Reflex angle
Explement (adds to 360°)
18°
Radians
19π/10 ≈ 5.969026
Open 342° in the online protractor

A 342° angle is a reflex angle: it is bigger than a straight line (180°) but less than a full turn (360°). It is the "outside" of an 18° angle: together they make a full 360° circle.

342° is 19/20 of a full circle, or 19π/10 radians. The minute hand of a clock sweeps 342° in 57 minutes. If you face north and turn 342° clockwise, you end up facing between NNW and N (closest to north-northwest (NNW)).

342° angle facts

Angle type Reflex angle (between 180° and 360°)
Explement (adds to 360°) 18°
Radians 19π/10 ≈ 5.969026
Gradians 380 grad
Fraction of a turn 19/20 (95%)
Degrees, minutes, seconds 342° 0′ 0″
Compass bearing between NNW and N (closest to north-northwest (NNW))

Trigonometric values of 342°

FunctionValue
sin 342° −(√5 − 1)/4 ≈ −0.309017
cos 342° √(10 + 2√5)/4 ≈ 0.951057
tan 342° −0.32492

342° on a protractor

Protractor showing 342 degrees0102030405060708090100110120130140150160170180190200210220230240250260270280290300310320330340350342°
On a 360° protractor, read 342° directly going counter-clockwise from 0°. Try it in the interactive protractor →

How to draw a 342° angle with a protractor

  1. Subtract from 360°: 360° − 342° = 18°. A standard protractor only goes to 180°, so you draw the smaller angle first.
  2. Draw a straight line with a ruler and mark the vertex at one end.
  3. Place the protractor's center mark on the vertex, line up the 0° baseline with your line, and make a dot at 18°.
  4. Join the vertex to the dot. The inside angle is 18°; the outside angle, going the long way around, is 342°. Draw the angle arc on the outside and label it 342°.
  5. With a 360° protractor you can skip the subtraction: put 0° on your first line and mark 342° directly.

Drawing it a 342° angle without a protractor (rise and run method)

  1. Draw a straight baseline and measure exactly 10 inches along it from the vertex.
  2. At the 10-inch mark, draw a short line straight up at 90° (use a carpenter's square or the corner of a sheet of paper).
  3. Measure 3.25 inches (about 3 1/4″) up that line and make a mark.
  4. Join the mark to the vertex. The angle at the vertex is 18°, because tan 18° ≈ 0.3249.
  5. That gives you 18°. The outside (reflex) angle is 342°.

Where you see 342° angles

  • The Earth turns 342° on its axis in about 22 h 48 min.
  • A 342° reflex angle is what you measure when you go the "long way" around, like the outside corner of a building or a turn of more than half a circle.

342° angle FAQ

What type of angle is 342°?

A 342° angle is a reflex angle, because it is between 180° and 360°.

Does a 342° angle have a complement or supplement?

No. Complements add up to 90° and supplements to 180°, and 342° is already larger than both. What it does have is an explement (conjugate) of 18°, the angle that completes a full 360° circle.

How many radians is 342 degrees?

342° = 19π/10 radians ≈ 5.969 rad. To convert degrees to radians, multiply by π/180: 342 × π/180 = 19π/10.

How do I measure a 342° angle on my screen?

Open the online protractor with 342° preset, or type 342 into its "Type an angle" box. You can then drag the arms onto your own lines to compare.