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: sairly
cipher variations:
tbjsmz ucktna vdluob wemvpc xfnwqd
ygoxre zhpysf aiqztg bjrauh cksbvi
dltcwj emudxk fnveyl gowfzm hpxgan
iqyhbo jrzicp ksajdq ltbker muclfs
nvdmgt owenhu pxfoiv qygpjw rzhqkx

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: sairly
Cipher: hzriob

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: sairly

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: sairly
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: sairly
Cipher: fnveyl

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: sairly
Cipher: 341142241345

Extended Methods:
Method #1

Plaintext: sairly
method variations:

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

Read more ...
Method #3

Plaintext: sairly
method variations:
dqgdsp qgdspd gdspdq
dspdqg spdqgd pdqgds

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: sairly

all 720 cipher variations:
sairly sairyl sailry sailyr saiylr saiyrl sarily sariyl sarliy sarlyi saryli
saryil salriy salryi saliry saliyr salyir salyri sayrli sayril saylri saylir
sayilr sayirl siarly siaryl sialry sialyr siaylr siayrl siraly sirayl sirlay
sirlya siryla siryal silray silrya silary silayr silyar silyra siyrla siyral
siylra siylar siyalr siyarl srialy sriayl srilay srilya sriyla sriyal sraily
sraiyl sraliy sralyi srayli srayil srlaiy srlayi srliay srliya srlyia srlyai
sryali sryail srylai srylia sryila sryial sliray slirya sliary sliayr sliyar
sliyra slriay slriya slraiy slrayi slryai slryia slariy slaryi slairy slaiyr
slayir slayri slyrai slyria slyari slyair slyiar slyira syirla syiral syilra
syilar syialr syiarl syrila syrial syrlia syrlai syrali syrail sylria sylrai
sylira syliar sylair sylari syarli syaril syalri syalir syailr syairl asirly
asiryl asilry asilyr asiylr asiyrl asrily asriyl asrliy asrlyi asryli asryil
aslriy aslryi asliry asliyr aslyir aslyri asyrli asyril asylri asylir asyilr
asyirl aisrly aisryl aislry aislyr aisylr aisyrl airsly airsyl airlsy airlys
airyls airysl ailrsy ailrys ailsry ailsyr ailysr ailyrs aiyrls aiyrsl aiylrs
aiylsr aiyslr aiysrl arisly arisyl arilsy arilys ariyls ariysl arsily arsiyl
arsliy arslyi arsyli arsyil arlsiy arlsyi arlisy arliys arlyis arlysi arysli
arysil arylsi arylis aryils aryisl alirsy alirys alisry alisyr aliysr aliyrs
alrisy alriys alrsiy alrsyi alrysi alryis alsriy alsryi alsiry alsiyr alsyir
alsyri alyrsi alyris alysri alysir alyisr alyirs ayirls ayirsl ayilrs ayilsr
ayislr ayisrl ayrils ayrisl ayrlis ayrlsi ayrsli ayrsil aylris aylrsi aylirs
aylisr aylsir aylsri aysrli aysril ayslri ayslir aysilr aysirl iasrly iasryl
iaslry iaslyr iasylr iasyrl iarsly iarsyl iarlsy iarlys iaryls iarysl ialrsy
ialrys ialsry ialsyr ialysr ialyrs iayrls iayrsl iaylrs iaylsr iayslr iaysrl
isarly isaryl isalry isalyr isaylr isayrl israly israyl isrlay isrlya isryla
isryal islray islrya islary islayr islyar islyra isyrla isyral isylra isylar
isyalr isyarl irsaly irsayl irslay irslya irsyla irsyal irasly irasyl iralsy
iralys irayls iraysl irlasy irlays irlsay irlsya irlysa irlyas iryals iryasl
irylas irylsa irysla irysal ilsray ilsrya ilsary ilsayr ilsyar ilsyra ilrsay
ilrsya ilrasy ilrays ilryas ilrysa ilarsy ilarys ilasry ilasyr ilaysr ilayrs
ilyras ilyrsa ilyars ilyasr ilysar ilysra iysrla iysral iyslra iyslar iysalr
iysarl iyrsla iyrsal iyrlsa iyrlas iyrals iyrasl iylrsa iylras iylsra iylsar
iylasr iylars iyarls iyarsl iyalrs iyalsr iyaslr iyasrl raisly raisyl railsy
railys raiyls raiysl rasily rasiyl rasliy raslyi rasyli rasyil ralsiy ralsyi
ralisy raliys ralyis ralysi raysli raysil raylsi raylis rayils rayisl riasly
riasyl rialsy rialys riayls riaysl risaly risayl rislay rislya risyla risyal
rilsay rilsya rilasy rilays rilyas rilysa riysla riysal riylsa riylas riyals
riyasl rsialy rsiayl rsilay rsilya rsiyla rsiyal rsaily rsaiyl rsaliy rsalyi
rsayli rsayil rslaiy rslayi rsliay rsliya rslyia rslyai rsyali rsyail rsylai
rsylia rsyila rsyial rlisay rlisya rliasy rliays rliyas rliysa rlsiay rlsiya
rlsaiy rlsayi rlsyai rlsyia rlasiy rlasyi rlaisy rlaiys rlayis rlaysi rlysai
rlysia rlyasi rlyais rlyias rlyisa ryisla ryisal ryilsa ryilas ryials ryiasl
rysila rysial ryslia ryslai rysali rysail rylsia rylsai rylisa rylias rylais
rylasi ryasli ryasil ryalsi ryalis ryails ryaisl lairsy lairys laisry laisyr
laiysr laiyrs larisy lariys larsiy larsyi larysi laryis lasriy lasryi lasiry
lasiyr lasyir lasyri layrsi layris laysri laysir layisr layirs liarsy liarys
liasry liasyr liaysr liayrs lirasy lirays lirsay lirsya lirysa liryas lisray
lisrya lisary lisayr lisyar lisyra liyrsa liyras liysra liysar liyasr liyars
lriasy lriays lrisay lrisya lriysa lriyas lraisy lraiys lrasiy lrasyi lraysi
lrayis lrsaiy lrsayi lrsiay lrsiya lrsyia lrsyai lryasi lryais lrysai lrysia
lryisa lryias lsiray lsirya lsiary lsiayr lsiyar lsiyra lsriay lsriya lsraiy
lsrayi lsryai lsryia lsariy lsaryi lsairy lsaiyr lsayir lsayri lsyrai lsyria
lsyari lsyair lsyiar lsyira lyirsa lyiras lyisra lyisar lyiasr lyiars lyrisa
lyrias lyrsia lyrsai lyrasi lyrais lysria lysrai lysira lysiar lysair lysari
lyarsi lyaris lyasri lyasir lyaisr lyairs yairls yairsl yailrs yailsr yaislr
yaisrl yarils yarisl yarlis yarlsi yarsli yarsil yalris yalrsi yalirs yalisr
yalsir yalsri yasrli yasril yaslri yaslir yasilr yasirl yiarls yiarsl yialrs
yialsr yiaslr yiasrl yirals yirasl yirlas yirlsa yirsla yirsal yilras yilrsa
yilars yilasr yilsar yilsra yisrla yisral yislra yislar yisalr yisarl yrials
yriasl yrilas yrilsa yrisla yrisal yrails yraisl yralis yralsi yrasli yrasil
yrlais yrlasi yrlias yrlisa yrlsia yrlsai yrsali yrsail yrslai yrslia yrsila
yrsial yliras ylirsa yliars yliasr ylisar ylisra ylrias ylrisa ylrais ylrasi
ylrsai ylrsia ylaris ylarsi ylairs ylaisr ylasir ylasri ylsrai ylsria ylsari
ylsair ylsiar ylsira ysirla ysiral ysilra ysilar ysialr ysiarl ysrila ysrial
ysrlia ysrlai ysrali ysrail yslria yslrai yslira ysliar yslair yslari ysarli
ysaril ysalri ysalir ysailr ysairl

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

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