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: cesaro
cipher variations:
dftbsp eguctq fhvdur giwevs hjxfwt
ikygxu jlzhyv kmaizw lnbjax mockby
npdlcz oqemda prfneb qsgofc rthpgd
suiqhe tvjrif uwksjg vxltkh wymuli
xznvmj yaownk zbpxol acqypm bdrzqn

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: cesaro
Cipher: xvhzil

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: cesaro

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: cesaro
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: cesaro
Cipher: prfneb

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: cesaro
Cipher: 315134112443

Extended Methods:
Method #1

Plaintext: cesaro
method variations:

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

Read more ...
Method #3

Plaintext: cesaro
method variations:
vldftn ldftnv dftnvl
ftnvld tnvldf nvldft

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: cesaro

all 720 cipher variations:
cesaro cesaor cesrao cesroa cesora cesoar ceasro ceasor cearso cearos ceaors
ceaosr ceraso ceraos cersao cersoa cerosa ceroas ceoars ceoasr ceoras ceorsa
ceosra ceosar csearo cseaor cserao cseroa cseora cseoar csaero csaeor csareo
csaroe csaore csaoer csraeo csraoe csreao csreoa csroea csroae csoare csoaer
csorae csorea csoera csoear casero caseor casreo casroe casore casoer caesro
caesor caerso caeros caeors caeosr careso careos carseo carsoe carose caroes
caoers caoesr caores caorse caosre caoser crsaeo crsaoe crseao crseoa crsoea
crsoae craseo crasoe craeso craeos craoes craose creaso creaos cresao cresoa
creosa creoas croaes croase croeas croesa crosea crosae cosare cosaer cosrae
cosrea cosera cosear coasre coaser coarse coares coaers coaesr corase coraes
corsae corsea coresa coreas coears coeasr coeras coersa coesra coesar ecsaro
ecsaor ecsrao ecsroa ecsora ecsoar ecasro ecasor ecarso ecaros ecaors ecaosr
ecraso ecraos ecrsao ecrsoa ecrosa ecroas ecoars ecoasr ecoras ecorsa ecosra
ecosar escaro escaor escrao escroa escora escoar esacro esacor esarco esaroc
esaorc esaocr esraco esraoc esrcao esrcoa esroca esroac esoarc esoacr esorac
esorca esocra esocar eascro eascor easrco easroc easorc easocr eacsro eacsor
eacrso eacros eacors eacosr earcso earcos earsco earsoc earosc earocs eaocrs
eaocsr eaorcs eaorsc eaosrc eaoscr ersaco ersaoc erscao erscoa ersoca ersoac
erasco erasoc eracso eracos eraocs eraosc ercaso ercaos ercsao ercsoa ercosa
ercoas eroacs eroasc erocas erocsa erosca erosac eosarc eosacr eosrac eosrca
eoscra eoscar eoasrc eoascr eoarsc eoarcs eoacrs eoacsr eorasc eoracs eorsac
eorsca eorcsa eorcas eocars eocasr eocras eocrsa eocsra eocsar secaro secaor
secrao secroa secora secoar seacro seacor searco searoc seaorc seaocr seraco
seraoc sercao sercoa seroca seroac seoarc seoacr seorac seorca seocra seocar
scearo sceaor scerao sceroa sceora sceoar scaero scaeor scareo scaroe scaore
scaoer scraeo scraoe screao screoa scroea scroae scoare scoaer scorae scorea
scoera scoear sacero saceor sacreo sacroe sacore sacoer saecro saecor saerco
saeroc saeorc saeocr sareco sareoc sarceo sarcoe saroce saroec saoerc saoecr
saorec saorce saocre saocer srcaeo srcaoe srceao srceoa srcoea srcoae sraceo
sracoe sraeco sraeoc sraoec sraoce sreaco sreaoc srecao srecoa sreoca sreoac
sroaec sroace sroeac sroeca srocea srocae socare socaer socrae socrea socera
socear soacre soacer soarce soarec soaerc soaecr sorace soraec sorcae sorcea
soreca soreac soearc soeacr soerac soerca soecra soecar aescro aescor aesrco
aesroc aesorc aesocr aecsro aecsor aecrso aecros aecors aecosr aercso aercos
aersco aersoc aerosc aerocs aeocrs aeocsr aeorcs aeorsc aeosrc aeoscr asecro
asecor aserco aseroc aseorc aseocr ascero asceor ascreo ascroe ascore ascoer
asrceo asrcoe asreco asreoc asroec asroce asocre asocer asorce asorec asoerc
asoecr acsero acseor acsreo acsroe acsore acsoer acesro acesor acerso aceros
aceors aceosr acreso acreos acrseo acrsoe acrose acroes acoers acoesr acores
acorse acosre acoser arsceo arscoe arseco arseoc arsoec arsoce arcseo arcsoe
arceso arceos arcoes arcose arecso arecos aresco aresoc areosc areocs aroces
arocse aroecs aroesc arosec arosce aoscre aoscer aosrce aosrec aoserc aosecr
aocsre aocser aocrse aocres aocers aocesr aorcse aorces aorsce aorsec aoresc
aorecs aoecrs aoecsr aoercs aoersc aoesrc aoescr resaco resaoc rescao rescoa
resoca resoac reasco reasoc reacso reacos reaocs reaosc recaso recaos recsao
recsoa recosa recoas reoacs reoasc reocas reocsa reosca reosac rseaco rseaoc
rsecao rsecoa rseoca rseoac rsaeco rsaeoc rsaceo rsacoe rsaoce rsaoec rscaeo
rscaoe rsceao rsceoa rscoea rscoae rsoace rsoaec rsocae rsocea rsoeca rsoeac
raseco raseoc rasceo rascoe rasoce rasoec raesco raesoc raecso raecos raeocs
raeosc raceso raceos racseo racsoe racose racoes raoecs raoesc raoces raocse
raosce raosec rcsaeo rcsaoe rcseao rcseoa rcsoea rcsoae rcaseo rcasoe rcaeso
rcaeos rcaoes rcaose rceaso rceaos rcesao rcesoa rceosa rceoas rcoaes rcoase
rcoeas rcoesa rcosea rcosae rosace rosaec roscae roscea roseca roseac roasce
roasec roacse roaces roaecs roaesc rocase rocaes rocsae rocsea rocesa roceas
roeacs roeasc roecas roecsa roesca roesac oesarc oesacr oesrac oesrca oescra
oescar oeasrc oeascr oearsc oearcs oeacrs oeacsr oerasc oeracs oersac oersca
oercsa oercas oecars oecasr oecras oecrsa oecsra oecsar osearc oseacr oserac
oserca osecra osecar osaerc osaecr osarec osarce osacre osacer osraec osrace
osreac osreca osrcea osrcae oscare oscaer oscrae oscrea oscera oscear oaserc
oasecr oasrec oasrce oascre oascer oaesrc oaescr oaersc oaercs oaecrs oaecsr
oaresc oarecs oarsec oarsce oarcse oarces oacers oacesr oacres oacrse oacsre
oacser orsaec orsace orseac orseca orscea orscae orasec orasce oraesc oraecs
oraces oracse oreasc oreacs oresac oresca orecsa orecas orcaes orcase orceas
orcesa orcsea orcsae ocsare ocsaer ocsrae ocsrea ocsera ocsear ocasre ocaser
ocarse ocares ocaers ocaesr ocrase ocraes ocrsae ocrsea ocresa ocreas ocears
oceasr oceras ocersa ocesra ocesar

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

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