DIAMETER TO AREA CONVERSION

DIAMETER TO AREA CONVERSION

Diameter

Square

Diameter

Square

   Diameter

    Square

Inches

Inches

Inches

Inches

Inches

Inches

1

0.7854

5

19.6350

9

63.6170

1-1/8

0.9940

5-1/8

20.6290

9-1/8

65.3970

1-1/4

1.2272

5-1/4

21.6480

9-1/4

67.2010

1-3/8

1.4849

5-3/8

22.6910

9-3/8

69.0290

1-1/2

1.7671

5-1/2

23.7580

9-1/2

70.8820

1-5/8

2.0739

5-5/8

24.8500

9-5/8

72.7600

1-3/4

2.4053

5-3/4

25.9670

9-3/4

74.6620

1-7/8

2.7612

5-7/8

27.1090

9-7/8

76.5890

2

3.1416

6

28.2740

10

78.5400

2-1/8

3.5466

6-1/8

29.4650

10-1/8

80.5160

2-1/4

3.0761

6-1/4

30.6800

10-1/4

82.5160

2-3/8

4.4301

6-3/8

31.9190

10-3/8

94.5410

2-1/2

4.9087

6-1/2

33.1830

10-1/2

86.5900

2-5/8

5.4119

6-5/8

34.4720

10-5/8

88.6640

2-3/4

5.9396

6-3/4

35.7850

10-3/4

90.7630

2-7/8

6.4918

6-7/8

37.1220

10-718

92.8860

3

7.0686

7

38.4850

11

95.0330

3-1/8

7.6699

7 -1/8

39.8710

11-1/8

97.2050

3-1/4

8.2958

7-1/4

41.2820

11-1/4

99.4020

3-3/8

8.9462

7-318

42.7180

11-3/8

101.6200

3-1/2

9.6211

7-1/2

44.1790

11-1/2

103.8700

3-5/8

10.3210

7-518

45.6640

11-5/8

106.1400

3-3/4

11.0450

7-314

47.1730

11-3/4

108.4300

3-7/8

11.7930

7-7/8

48.7070

11-7/8

110.7500

4

12.5660

8

50.2650

12

113.1000

4-1/8

13.3640

8-1/8

51.8490

To obtain area for any other diameters, use this formula:

Dia. X Dia. X .7854

4-1/4

14.1860

8-1/4

53.4560

4-3/8

15.0330

8-3/8

55.0880

4-1/2

15.9040

8-1/2

56.7 450

4-5/8

16.8000

8-5/8

58.4260

4-3/4

17.7210

8-3/4

30.1320

4-7/8

18.6650

8-718

61.8620