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: solver
cipher variations:
tpmwfs uqnxgt vroyhu wspziv xtqajw
yurbkx zvscly awtdmz bxuena cyvfob
dzwgpc eaxhqd fbyire gczjsf hdaktg
iebluh jfcmvi kgdnwj lheoxk mifpyl
njgqzm okhran plisbo qmjtcp rnkudq

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: solver
Cipher: hloevi

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: solver

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: solver
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: solver
Cipher: fbyire

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: solver
Cipher: 344313155124

Extended Methods:
Method #1

Plaintext: solver
method variations:

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

Read more ...
Method #3

Plaintext: solver
method variations:
tcczfo cczfot czfotc
zfotcc fotccz otcczf

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: solver

all 720 cipher variations:
solver solvre solevr solerv solrev solrve sovler sovlre sovelr soverl sovrel
sovrle soevlr soevrl soelvr soelrv soerlv soervl sorvel sorvle sorevl sorelv
sorlev sorlve slover slovre sloevr sloerv slorev slorve slvoer slvore slveor
slvero slvreo slvroe slevor slevro sleovr sleorv slerov slervo slrveo slrvoe
slrevo slreov slroev slrove svloer svlore svleor svlero svlreo svlroe svoler
svolre svoelr svoerl svorel svorle sveolr sveorl svelor svelro sverlo sverol
svroel svrole svreol svrelo svrleo svrloe selvor selvro selovr selorv selrov
selrvo sevlor sevlro sevolr sevorl sevrol sevrlo seovlr seovrl seolvr seolrv
seorlv seorvl servol servlo serovl serolv serlov serlvo srlveo srlvoe srlevo
srleov srloev srlove srvleo srvloe srvelo srveol srvoel srvole srevlo srevol
srelvo srelov sreolv sreovl srovel srovle sroevl sroelv srolev srolve oslver
oslvre oslevr oslerv oslrev oslrve osvler osvlre osvelr osverl osvrel osvrle
osevlr osevrl oselvr oselrv oserlv oservl osrvel osrvle osrevl osrelv osrlev
osrlve olsver olsvre olsevr olserv olsrev olsrve olvser olvsre olvesr olvers
olvres olvrse olevsr olevrs olesvr olesrv olersv olervs olrves olrvse olrevs
olresv olrsev olrsve ovlser ovlsre ovlesr ovlers ovlres ovlrse ovsler ovslre
ovselr ovserl ovsrel ovsrle oveslr ovesrl ovelsr ovelrs overls oversl ovrsel
ovrsle ovresl ovrels ovrles ovrlse oelvsr oelvrs oelsvr oelsrv oelrsv oelrvs
oevlsr oevlrs oevslr oevsrl oevrsl oevrls oesvlr oesvrl oeslvr oeslrv oesrlv
oesrvl oervsl oervls oersvl oerslv oerlsv oerlvs orlves orlvse orlevs orlesv
orlsev orlsve orvles orvlse orvels orvesl orvsel orvsle orevls orevsl orelvs
orelsv oreslv oresvl orsvel orsvle orsevl orselv orslev orslve losver losvre
losevr loserv losrev losrve lovser lovsre lovesr lovers lovres lovrse loevsr
loevrs loesvr loesrv loersv loervs lorves lorvse lorevs loresv lorsev lorsve
lsover lsovre lsoevr lsoerv lsorev lsorve lsvoer lsvore lsveor lsvero lsvreo
lsvroe lsevor lsevro lseovr lseorv lserov lservo lsrveo lsrvoe lsrevo lsreov
lsroev lsrove lvsoer lvsore lvseor lvsero lvsreo lvsroe lvoser lvosre lvoesr
lvoers lvores lvorse lveosr lveors lvesor lvesro lverso lveros lvroes lvrose
lvreos lvreso lvrseo lvrsoe lesvor lesvro lesovr lesorv lesrov lesrvo levsor
levsro levosr levors levros levrso leovsr leovrs leosvr leosrv leorsv leorvs
lervos lervso lerovs lerosv lersov lersvo lrsveo lrsvoe lrsevo lrseov lrsoev
lrsove lrvseo lrvsoe lrveso lrveos lrvoes lrvose lrevso lrevos lresvo lresov
lreosv lreovs lroves lrovse lroevs lroesv lrosev lrosve volser volsre volesr
volers volres volrse vosler voslre voselr voserl vosrel vosrle voeslr voesrl
voelsr voelrs voerls voersl vorsel vorsle voresl vorels vorles vorlse vloser
vlosre vloesr vloers vlores vlorse vlsoer vlsore vlseor vlsero vlsreo vlsroe
vlesor vlesro vleosr vleors vleros vlerso vlrseo vlrsoe vlreso vlreos vlroes
vlrose vsloer vslore vsleor vslero vslreo vslroe vsoler vsolre vsoelr vsoerl
vsorel vsorle vseolr vseorl vselor vselro vserlo vserol vsroel vsrole vsreol
vsrelo vsrleo vsrloe velsor velsro velosr velors velros velrso veslor veslro
vesolr vesorl vesrol vesrlo veoslr veosrl veolsr veolrs veorls veorsl versol
verslo verosl verols verlos verlso vrlseo vrlsoe vrleso vrleos vrloes vrlose
vrsleo vrsloe vrselo vrseol vrsoel vrsole vreslo vresol vrelso vrelos vreols
vreosl vrosel vrosle vroesl vroels vroles vrolse eolvsr eolvrs eolsvr eolsrv
eolrsv eolrvs eovlsr eovlrs eovslr eovsrl eovrsl eovrls eosvlr eosvrl eoslvr
eoslrv eosrlv eosrvl eorvsl eorvls eorsvl eorslv eorlsv eorlvs elovsr elovrs
elosvr elosrv elorsv elorvs elvosr elvors elvsor elvsro elvrso elvros elsvor
elsvro elsovr elsorv elsrov elsrvo elrvso elrvos elrsvo elrsov elrosv elrovs
evlosr evlors evlsor evlsro evlrso evlros evolsr evolrs evoslr evosrl evorsl
evorls evsolr evsorl evslor evslro evsrlo evsrol evrosl evrols evrsol evrslo
evrlso evrlos eslvor eslvro eslovr eslorv eslrov eslrvo esvlor esvlro esvolr
esvorl esvrol esvrlo esovlr esovrl esolvr esolrv esorlv esorvl esrvol esrvlo
esrovl esrolv esrlov esrlvo erlvso erlvos erlsvo erlsov erlosv erlovs ervlso
ervlos ervslo ervsol ervosl ervols ersvlo ersvol erslvo erslov ersolv ersovl
erovsl erovls erosvl eroslv erolsv erolvs rolves rolvse rolevs rolesv rolsev
rolsve rovles rovlse rovels rovesl rovsel rovsle roevls roevsl roelvs roelsv
roeslv roesvl rosvel rosvle rosevl roselv roslev roslve rloves rlovse rloevs
rloesv rlosev rlosve rlvoes rlvose rlveos rlveso rlvseo rlvsoe rlevos rlevso
rleovs rleosv rlesov rlesvo rlsveo rlsvoe rlsevo rlseov rlsoev rlsove rvloes
rvlose rvleos rvleso rvlseo rvlsoe rvoles rvolse rvoels rvoesl rvosel rvosle
rveols rveosl rvelos rvelso rveslo rvesol rvsoel rvsole rvseol rvselo rvsleo
rvsloe relvos relvso relovs relosv relsov relsvo revlos revlso revols revosl
revsol revslo reovls reovsl reolvs reolsv reoslv reosvl resvol resvlo resovl
resolv reslov reslvo rslveo rslvoe rslevo rsleov rsloev rslove rsvleo rsvloe
rsvelo rsveol rsvoel rsvole rsevlo rsevol rselvo rselov rseolv rseovl rsovel
rsovle rsoevl rsoelv rsolev rsolve

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

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