easy ciphers

Easy Ciphers Tools:
cryptography lectures
popular ciphers:



















Caesar cipher

Caesar cipher, is one of the simplest and most widely known encryption techniques. The transformation can be represented by aligning two alphabets, the cipher alphabet is the plain alphabet rotated left or right by some number of positions.

When encrypting, a person looks up each letter of the message in the 'plain' line and writes down the corresponding letter in the 'cipher' line. Deciphering is done in reverse.
The encryption can also be represented using modular arithmetic by first transforming the letters into numbers, according to the scheme, A = 0, B = 1,..., Z = 25. Encryption of a letter x by a shift n can be described mathematically as

Plaintext: mishoe
cipher variations:
njtipf okujqg plvkrh qmwlsi rnxmtj
soynuk tpzovl uqapwm vrbqxn wscryo
xtdszp yuetaq zvfubr awgvcs bxhwdt
cyixeu dzjyfv eakzgw fblahx gcmbiy
hdncjz ieodka jfpelb kgqfmc lhrgnd

Decryption is performed similarly,

(There are different definitions for the modulo operation. In the above, the result is in the range 0...25. I.e., if x+n or x-n are not in the range 0...25, we have to subtract or add 26.)
Read more ...
Atbash Cipher

Atbash is an ancient encryption system created in the Middle East. It was originally used in the Hebrew language.
The Atbash cipher is a simple substitution cipher that relies on transposing all the letters in the alphabet such that the resulting alphabet is backwards.
The first letter is replaced with the last letter, the second with the second-last, and so on.
An example plaintext to ciphertext using Atbash:
Plain: mishoe
Cipher: nrhslv

Read more ...


Baconian Cipher

To encode a message, each letter of the plaintext is replaced by a group of five of the letters 'A' or 'B'. This replacement is done according to the alphabet of the Baconian cipher, shown below.
a   AAAAA   g    AABBA     m    ABABB   s    BAAAB     y    BABBA
b   AAAAB   h    AABBB     n    ABBAA   t    BAABA     z    BABBB
c   AAABA   i    ABAAA     o    ABBAB   u    BAABB 
d   AAABB   j    BBBAA     p    ABBBA   v    BBBAB
e   AABAA   k    ABAAB     q    ABBBB   w    BABAA
f   AABAB   l    ABABA     r    BAAAA   x    BABAB

Plain: mishoe

Read more ...


Affine Cipher
In the affine cipher the letters of an alphabet of size m are first mapped to the integers in the range 0..m - 1. It then uses modular arithmetic to transform the integer that each plaintext letter corresponds to into another integer that correspond to a ciphertext letter. The encryption function for a single letter is

where modulus m is the size of the alphabet and a and b are the key of the cipher. The value a must be chosen such that a and m are coprime.
Considering the specific case of encrypting messages in English (i.e. m = 26), there are a total of 286 non-trivial affine ciphers, not counting the 26 trivial Caesar ciphers. This number comes from the fact there are 12 numbers that are coprime with 26 that are less than 26 (these are the possible values of a). Each value of a can have 26 different addition shifts (the b value) ; therefore, there are 12*26 or 312 possible keys.
Plaintext: mishoe
cipher variations:

The decryption function is

where a - 1 is the modular multiplicative inverse of a modulo m. I.e., it satisfies the equation

The multiplicative inverse of a only exists if a and m are coprime. Hence without the restriction on a decryption might not be possible. It can be shown as follows that decryption function is the inverse of the encryption function,

Read more ...


ROT13 Cipher
Applying ROT13 to a piece of text merely requires examining its alphabetic characters and replacing each one by the letter 13 places further along in the alphabet, wrapping back to the beginning if necessary. A becomes N, B becomes O, and so on up to M, which becomes Z, then the sequence continues at the beginning of the alphabet: N becomes A, O becomes B, and so on to Z, which becomes M. Only those letters which occur in the English alphabet are affected; numbers, symbols, whitespace, and all other characters are left unchanged. Because there are 26 letters in the English alphabet and 26 = 2 * 13, the ROT13 function is its own inverse:

ROT13(ROT13(x)) = x for any basic Latin-alphabet text x

An example plaintext to ciphertext using ROT13:

Plain: mishoe
Cipher: zvfubr

Read more ...


Polybius Square

A Polybius Square is a table that allows someone to translate letters into numbers. To give a small level of encryption, this table can be randomized and shared with the recipient. In order to fit the 26 letters of the alphabet into the 25 spots created by the table, the letters i and j are usually combined.
1 2 3 4 5
1 A B C D E
2 F G H I/J K
3 L M N O P
4 Q R S T U
5 V W X Y Z

Basic Form:
Plain: mishoe
Cipher: 234234324351

Extended Methods:
Method #1

Plaintext: mishoe
method variations:

Method #2
Bifid cipher
The message is converted to its coordinates in the usual manner, but they are written vertically beneath:
m i s h o e 
2 4 3 3 4 5 
3 2 4 2 3 1 
They are then read out in rows:
Then divided up into pairs again, and the pairs turned back into letters using the square:
Plain: mishoe
Cipher: rnyhic

Read more ...
Method #3

Plaintext: mishoe
method variations:
smorxf morxfs orxfsm
rxfsmo xfsmor fsmorx

Read more ...[RUS] , [EN]


Permutation Cipher
In classical cryptography, a permutation cipher is a transposition cipher in which the key is a permutation. To apply a cipher, a random permutation of size E is generated (the larger the value of E the more secure the cipher). The plaintext is then broken into segments of size E and the letters within that segment are permuted according to this key.
In theory, any transposition cipher can be viewed as a permutation cipher where E is equal to the length of the plaintext; this is too cumbersome a generalisation to use in actual practice, however.
The idea behind a permutation cipher is to keep the plaintext characters unchanged, butalter their positions by rearrangement using a permutation
This cipher is defined as:
Let m be a positive integer, and K consist of all permutations of {1,...,m}
For a key (permutation) , define:
The encryption function
The decryption function
A small example, assuming m = 6, and the key is the permutation :

The first row is the value of i, and the second row is the corresponding value of (i)
The inverse permutation, is constructed by interchanging the two rows, andrearranging the columns so that the first row is in increasing order, Therefore, is:

Total variation formula:

e = 2,718281828 , n - plaintext length

Plaintext: mishoe

all 720 cipher variations:
mishoe misheo misohe misoeh miseoh miseho mihsoe mihseo mihose mihoes miheos
miheso miohse miohes mioshe mioseh mioesh mioehs miehos miehso mieohs mieosh
miesoh miesho msihoe msiheo msiohe msioeh msieoh msieho mshioe mshieo mshoie
mshoei msheoi msheio msohie msohei msoihe msoieh msoeih msoehi msehoi msehio
mseohi mseoih mseioh mseiho mhsioe mhsieo mhsoie mhsoei mhseoi mhseio mhisoe
mhiseo mhiose mhioes mhieos mhieso mhoise mhoies mhosie mhosei mhoesi mhoeis
mheios mheiso mheois mheosi mhesoi mhesio moshie moshei mosihe mosieh moseih
mosehi mohsie mohsei mohise mohies moheis mohesi moihse moihes moishe moiseh
moiesh moiehs moehis moehsi moeihs moeish moesih moeshi meshoi meshio mesohi
mesoih mesioh mesiho mehsoi mehsio mehosi mehois mehios mehiso meohsi meohis
meoshi meosih meoish meoihs meihos meihso meiohs meiosh meisoh meisho imshoe
imsheo imsohe imsoeh imseoh imseho imhsoe imhseo imhose imhoes imheos imheso
imohse imohes imoshe imoseh imoesh imoehs imehos imehso imeohs imeosh imesoh
imesho ismhoe ismheo ismohe ismoeh ismeoh ismeho ishmoe ishmeo ishome ishoem
isheom ishemo isohme isohem isomhe isomeh isoemh isoehm isehom isehmo iseohm
iseomh isemoh isemho ihsmoe ihsmeo ihsome ihsoem ihseom ihsemo ihmsoe ihmseo
ihmose ihmoes ihmeos ihmeso ihomse ihomes ihosme ihosem ihoesm ihoems ihemos
ihemso iheoms iheosm ihesom ihesmo ioshme ioshem iosmhe iosmeh iosemh iosehm
iohsme iohsem iohmse iohmes iohems iohesm iomhse iomhes iomshe iomseh iomesh
iomehs ioehms ioehsm ioemhs ioemsh ioesmh ioeshm ieshom ieshmo iesohm iesomh
iesmoh iesmho iehsom iehsmo iehosm iehoms iehmos iehmso ieohsm ieohms ieoshm
ieosmh ieomsh ieomhs iemhos iemhso iemohs iemosh iemsoh iemsho simhoe simheo
simohe simoeh simeoh simeho sihmoe sihmeo sihome sihoem siheom sihemo siohme
siohem siomhe siomeh sioemh sioehm siehom siehmo sieohm sieomh siemoh siemho
smihoe smiheo smiohe smioeh smieoh smieho smhioe smhieo smhoie smhoei smheoi
smheio smohie smohei smoihe smoieh smoeih smoehi smehoi smehio smeohi smeoih
smeioh smeiho shmioe shmieo shmoie shmoei shmeoi shmeio shimoe shimeo shiome
shioem shieom shiemo shoime shoiem shomie shomei shoemi shoeim sheiom sheimo
sheoim sheomi shemoi shemio somhie somhei somihe somieh someih somehi sohmie
sohmei sohime sohiem soheim sohemi soihme soihem soimhe soimeh soiemh soiehm
soehim soehmi soeihm soeimh soemih soemhi semhoi semhio semohi semoih semioh
semiho sehmoi sehmio sehomi sehoim sehiom sehimo seohmi seohim seomhi seomih
seoimh seoihm seihom seihmo seiohm seiomh seimoh seimho hismoe hismeo hisome
hisoem hiseom hisemo himsoe himseo himose himoes himeos himeso hiomse hiomes
hiosme hiosem hioesm hioems hiemos hiemso hieoms hieosm hiesom hiesmo hsimoe
hsimeo hsiome hsioem hsieom hsiemo hsmioe hsmieo hsmoie hsmoei hsmeoi hsmeio
hsomie hsomei hsoime hsoiem hsoeim hsoemi hsemoi hsemio hseomi hseoim hseiom
hseimo hmsioe hmsieo hmsoie hmsoei hmseoi hmseio hmisoe hmiseo hmiose hmioes
hmieos hmieso hmoise hmoies hmosie hmosei hmoesi hmoeis hmeios hmeiso hmeois
hmeosi hmesoi hmesio hosmie hosmei hosime hosiem hoseim hosemi homsie homsei
homise homies homeis homesi hoimse hoimes hoisme hoisem hoiesm hoiems hoemis
hoemsi hoeims hoeism hoesim hoesmi hesmoi hesmio hesomi hesoim hesiom hesimo
hemsoi hemsio hemosi hemois hemios hemiso heomsi heomis heosmi heosim heoism
heoims heimos heimso heioms heiosm heisom heismo oishme oishem oismhe oismeh
oisemh oisehm oihsme oihsem oihmse oihmes oihems oihesm oimhse oimhes oimshe
oimseh oimesh oimehs oiehms oiehsm oiemhs oiemsh oiesmh oieshm osihme osihem
osimhe osimeh osiemh osiehm oshime oshiem oshmie oshmei oshemi osheim osmhie
osmhei osmihe osmieh osmeih osmehi osehmi osehim osemhi osemih oseimh oseihm
ohsime ohsiem ohsmie ohsmei ohsemi ohseim ohisme ohisem ohimse ohimes ohiems
ohiesm ohmise ohmies ohmsie ohmsei ohmesi ohmeis oheims oheism ohemis ohemsi
ohesmi ohesim omshie omshei omsihe omsieh omseih omsehi omhsie omhsei omhise
omhies omheis omhesi omihse omihes omishe omiseh omiesh omiehs omehis omehsi
omeihs omeish omesih omeshi oeshmi oeshim oesmhi oesmih oesimh oesihm oehsmi
oehsim oehmsi oehmis oehims oehism oemhsi oemhis oemshi oemsih oemish oemihs
oeihms oeihsm oeimhs oeimsh oeismh oeishm eishom eishmo eisohm eisomh eismoh
eismho eihsom eihsmo eihosm eihoms eihmos eihmso eiohsm eiohms eioshm eiosmh
eiomsh eiomhs eimhos eimhso eimohs eimosh eimsoh eimsho esihom esihmo esiohm
esiomh esimoh esimho eshiom eshimo eshoim eshomi eshmoi eshmio esohim esohmi
esoihm esoimh esomih esomhi esmhoi esmhio esmohi esmoih esmioh esmiho ehsiom
ehsimo ehsoim ehsomi ehsmoi ehsmio ehisom ehismo ehiosm ehioms ehimos ehimso
ehoism ehoims ehosim ehosmi ehomsi ehomis ehmios ehmiso ehmois ehmosi ehmsoi
ehmsio eoshim eoshmi eosihm eosimh eosmih eosmhi eohsim eohsmi eohism eohims
eohmis eohmsi eoihsm eoihms eoishm eoismh eoimsh eoimhs eomhis eomhsi eomihs
eomish eomsih eomshi emshoi emshio emsohi emsoih emsioh emsiho emhsoi emhsio
emhosi emhois emhios emhiso emohsi emohis emoshi emosih emoish emoihs emihos
emihso emiohs emiosh emisoh emisho

Read more ...[1] , [2] , [3]

History of cryptography
2011 Easy Ciphers. All rights reserved. contact us