Tank Capacity or Tank Length Estimator - Instructions

Note: You must have the tank diameter and either the tank length or tank capacity. These approximate estimates are for flat tank heads.

To find the approximate tank capacity:
  1. Determine the diameter of the tank.
  2. In the chart column "Tank Diameter (Feet/Inches)", find the corresponding "gals/ft of length" in the Tank Capacity (Gallons) column.
  3. Multiply the tank length in feet by this "gals/ft of length". This is the approximate tank capacity.
To find the approximate tank length:
  1. Determine the diameter of the tank.
  2. In the chart column "Tank Diameter (Feet/Inches)", find the corresponding "gals/ft of length" in the Tank Capacity (Gallons) column.
  3. Divide the tank capacity by the "gals/ft of length". This is the approximate tank length.

U.S. Gallons in a Round Tank for One Foot in Length
Tank Diameter
(Feet/Inches)
Tank Capacity
(Gallons)
TankVolume
(Cubic Feet)
1’
1’1”
1’2”
1’3”
1’4”
1’5”
1’6”
1’7”
1’8”
1’9”
1’10”
1’11”

2’
2’1”
2’2”
2’3”
2’4”
2’5”
2’6”
2’7”
2’8”
2’9”
2’10”
2’11”

3’
3’1”
3’2”
3’3”
3’4”
3’5”
3’6”
3’7”
3’8”
3’9”
3’10”
3’11”

4’
4’1”
4’2”
4’3”
4’4”
4’5”
4’6”
4’7”
4’8”
4’9”
4’10”
4’11”

5’
5’1”
5’2”
5’3”
5’4”
5’5”
5’6”
5’7”
5’8”
5’9”
5’10”
5’11”

6’
6’3”
6’6”
6’9”

7’
7’3”
7’6”
7’9”

8’
8’3”
8’6”
8’9”

9’
9’3”
9’6”
9’9”

10
10’3”
10’6”
10’9”

11’
11’3”
11’6”
11’9”

12
12’3”
12’6”
12’9”

13’
13’3”
13’6”
13’9”

14’
5.87
6.89
8.00
9.18
10.44
11.79
13.22
14.73
16.32
17.99
19.75
21.58

23.50
25.50
27.58
29.74
31.99
34.31
36.72
39.21
41.78
44.43
47.16
49.98

52.88
55.86
58.92
62.06
65.28
68.58
71.97
75.44
78.99
82.62
86.33
90.13

94.00
97.96
102.00
106.12
110.32
114.61
118.07
123.42
127.95
132.56
137.25
142.02

146.88
151.82
156.83
161.93
167.12
172.38
177.72
185.15
188.66
194.25
199.92
205.67

211.51
229.50
248.23
267.69

287.88
308.81
330.48
352.88

376.01
399.88
424.48
449.52

475.89
502.70
530.24
558.51

587.52
617.26
640.74
678.95

710.90
743.58
776.99
811.14

846.03
881.65
918.00
955.09

992.91
1031.50
1070.80
1110.80

1151.50
.785
.922
1.069
1.227
1.396
1.576
1.767
1.969
2.182
2.405
2.640
2.885

3.142
3.409
3.686
3.976
4.276
4.587
4.909
5.241
5.585
5.940
6.305
6.681

7.069
7.467
7.876
8.296
8.727
9.168
9.621
10.085
10.559
11.045
11.541
12.048

12.566
13.095
13.635
14.186
14.748
15.321
15.90
16.50
17.10
17.72
18.35
18.99

19.63
20.29
20.97
21.65
22.34
23.04
23.76
24.48
25.22
25.97
26.73
27.49

28.27
30.68
33.18
35.78

38.48
41.28
44.18
47.17

50.27
53.46
56.75
60.13

63.62
67.20
70.88
74.66

78.54
82.52
86.59
90.76

95.03
99.40
103.87
108.43

113.10
117.86
122.72
127.68

132.73
137.89
143.14
148.49

153.94