Forgot your scale? Guess what there is a way that you can get the average weight of the bass that you caught. Just measure the length, and then the girth. The girth is the length around the largest part of the body of a bass. You can then manually use the formula below to calculate the approximate weight of your Largemouth or Smallmouth bass. You can also use the weight calculator below.

(Length X Length) X Girth ÷ 1200

Length Weight
(inches) (.01th) (ounces)
12.00.......0.82........0.13
12.25.......0.88........0.14
12.50.......0.94........0.15
12.75.......1.01........1.00
13.00.......1.07........1.01
13.25.......1.15........1.02
13.50.......1.22........1.04
13.75.......1.30........1.05
14.00.......1.38........1.06
14.25.......1.47........1.08
14.50.......1.55........1.09
14.75.......1.65........1.10
15.00.......1.74........1.12
15.25.......1.84........1.13
15.50.......1.95........1.15
15.75.......2.05........2.01
16.00.......2.17........2.03
16.25.......2.28........2.04
16.50.......2.40........2.06

 Length Weight
(inches) (.01th) (ounces)
16.75.......2.53........2.08
17.00.......2.66........2.11
17.25.......2.79........2.13
17.50.......2.93........2.15
17.75.......3.08........3.01
18.00.......3.25........3.04
18.25.......3.38........3.06
18.50.......3.54........3.09
18.75.......3.70........3.11
19.00.......3.87........3.14
19.25.......4.05........4.01
19.50.......4.23........4.04
19.75.......4.41........4.07
20.00.......4.60........4.10
20.25.......4.80........4.13
20.50.......5.00........5.00
20.75.......5.21........5.03
21.00.......5.43........5.07
21.25.......5.65........5.10

 Length Weight
(inches) (.01th) (ounces)
21.50......5.88........5.14
21.75......6.11........6.02
22.00......6.35........6.06
22.25......6.60........6.10
22.50......6.85........6.14
22.75......7.11........7.02
23.00......7.38........7.06
23.25......7.65........7.10
23.50......7.94........7.15
23.75......8.23........8.04
24.00......8.52........8.08
24.25......8.82........8.13
24.50......9.14........9.02
24.75......9.45........9.07
25.00......9.78........9.12
25.25.....10.11......10.02
25.50.....10.46......10.07
25.75.....10.81......10.13
26.00.....11.17......11.03 

If you know the length of your bass you can use the scale above to get a good idea of how much it weighed.