Szyfr Bacona jest szyfrem, w którym tekst zaszyfrowany zawiera pięcioliterowe ciągi złożone z liter a i b. Szyfrowanie i odszyfrowanie przebiega według schematu:
A = aaaaa
B = aaaab
C = aaaba
D = aaabb
E = aabaa
F = aabab
G = aabba
H = aabbb
I/J= abaaa
K = abaab
L = ababa
M = ababb
N = abbaa
O = abbab
P = abbba
Q = abbbb
R = baaaa
S = baaab
T = baaba
U/V= baabb
W = babaa
X = babab
Y = babba
Z = babbb
A = aaaaa
B = aaaab
C = aaaba
D = aaabb
E = aabaa
F = aabab
G = aabba
H = aabbb
I/J= abaaa
K = abaab
L = ababa
M = ababb
N = abbaa
O = abbab
P = abbba
Q = abbbb
R = baaaa
S = baaab
T = baaba
U/V= baabb
W = babaa
X = babab
Y = babba
Z = babbb