Acute angle

4 Degree Angle

π/45 ≈ 0.069813 radians · one ninetieth (1/90) (1.11%) of a circle

Diagram of a 4 degree angle4°
Acute angle: 4°

Key facts

4°

Angle type
Acute angle
Complement (adds to 90°)
86°
Supplement (adds to 180°)
176°
Explement (adds to 360°)
356°
Open 4° in the online protractor

At 4°, this angle is acute, meaning it is narrower than the corner of a square. It is a very narrow angle, just 4.4% of a right angle, the kind of small slope you see in drainage, ramps and fine adjustments.

4° is one ninetieth (1/90) of a full circle, or π/45 radians. If you face north and turn 4° clockwise, you end up facing between N and NNE (closest to north (N)).

4° angle facts

Angle type Acute angle (between 0° and 90°)
Complement (adds to 90°) 86°
Supplement (adds to 180°) 176°
Explement (adds to 360°) 356°
Radians π/45 ≈ 0.069813
Gradians 4.4444 grad
Fraction of a turn one ninetieth (1/90) (1.11%)
Degrees, minutes, seconds 4° 0′ 0″
Slope (grade) 6.99%
Roof pitch 0.84/12
Compass bearing between N and NNE (closest to north (N))

Trigonometric values of 4°

FunctionValue
sin 4° 0.069756
cos 4° 0.997564
tan 4° 0.069927

4° on a protractor

Protractor showing 4 degrees018010170201603015040140501306012070110801009090100801107012060130501404015030160201701018004°
On a 180° protractor, 4° is read on the scale that starts at 0° on the base arm. Try it in the interactive protractor →

How to draw a 4° angle with a protractor

  1. Draw a straight line with a ruler. This is the first arm; mark the vertex at one end.
  2. Place the center mark of the protractor exactly on the vertex and line up the 0° baseline with your line.
  3. Find 4° on the row of numbers that reads 0° on your line (protractors have two rows running in opposite directions) and make a small dot at the edge.
  4. Remove the protractor and draw a line from the vertex through the dot. Mark the angle with an arc and label it 4°.

Drawing it a 4° 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 0.7 inches (about 11/16″) up that line and make a mark.
  4. Join the mark to the vertex. The angle at the vertex is 4°, because tan 4° ≈ 0.0699.

Where you see 4° angles

  • The Leaning Tower of Pisa leans roughly 4° from vertical (about 3.97° since its stabilization work).
  • Divide a circle into 90 equal slices and each slice is 4°, e.g. 90 spokes on a wheel or 90 equal pie-chart wedges.
  • A 45-sided frame (45-sided polygon) is assembled with 4° miter cuts.
  • A board sloped at 4° rises about 8.4 inches over a 10-foot (120-inch) run.
  • 4° of latitude on Earth spans roughly 276 miles north to south.
  • The Earth turns 4° on its axis in about 16 minutes.

4° angle FAQ

What type of angle is 4°?

A 4° angle is an acute angle, because it is between 0° and 90°.

What are the complement and supplement of 4°?

The complement of 4° is 86° (together they make 90°), and the supplement is 176° (together they make 180°).

How many radians is 4 degrees?

4° = π/45 radians ≈ 0.0698 rad. To convert degrees to radians, multiply by π/180: 4 × π/180 = π/45.

What is 4° as a slope or roof pitch?

4° is a 7% slope, which is a roof pitch of 0.84/12 (a rise of about 7/8 inches for every 12 inches of run).