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: amebix
cipher variations:
bnfcjy cogdkz dphela eqifmb frjgnc
gskhod htlipe iumjqf jvnkrg kwolsh
lxpmti myqnuj nzrovk oaspwl pbtqxm
qcuryn rdvszo sewtap tfxubq ugyvcr
vhzwds wiaxet xjbyfu ykczgv zldahw

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: amebix
Cipher: znvyrc

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: amebix

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: amebix
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: amebix
Cipher: nzrovk

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: amebix
Cipher: 112351214235

Extended Methods:
Method #1

Plaintext: amebix
method variations:

Method #2
Bifid cipher
The message is converted to its coordinates in the usual manner, but they are written vertically beneath:
a m e b i x 
1 2 5 2 4 3 
1 3 1 1 2 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: amebix
Cipher: fkolaw

Read more ...
Method #3

Plaintext: amebix
method variations:
fxfqme xfqmef fqmefx
qmefxf mefxfq efxfqm

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: amebix

all 720 cipher variations:
amebix amebxi ameibx ameixb amexib amexbi ambeix ambexi ambiex ambixe ambxie
ambxei amibex amibxe amiebx amiexb amixeb amixbe amxbie amxbei amxibe amxieb
amxeib amxebi aembix aembxi aemibx aemixb aemxib aemxbi aebmix aebmxi aebimx
aebixm aebxim aebxmi aeibmx aeibxm aeimbx aeimxb aeixmb aeixbm aexbim aexbmi
aexibm aeximb aexmib aexmbi abemix abemxi abeimx abeixm abexim abexmi abmeix
abmexi abmiex abmixe abmxie abmxei abimex abimxe abiemx abiexm abixem abixme
abxmie abxmei abxime abxiem abxeim abxemi aiebmx aiebxm aiembx aiemxb aiexmb
aiexbm aibemx aibexm aibmex aibmxe aibxme aibxem aimbex aimbxe aimebx aimexb
aimxeb aimxbe aixbme aixbem aixmbe aixmeb aixemb aixebm axebim axebmi axeibm
axeimb axemib axembi axbeim axbemi axbiem axbime axbmie axbmei axibem axibme
axiebm axiemb aximeb aximbe axmbie axmbei axmibe axmieb axmeib axmebi maebix
maebxi maeibx maeixb maexib maexbi mabeix mabexi mabiex mabixe mabxie mabxei
maibex maibxe maiebx maiexb maixeb maixbe maxbie maxbei maxibe maxieb maxeib
maxebi meabix meabxi meaibx meaixb meaxib meaxbi mebaix mebaxi mebiax mebixa
mebxia mebxai meibax meibxa meiabx meiaxb meixab meixba mexbia mexbai mexiba
mexiab mexaib mexabi mbeaix mbeaxi mbeiax mbeixa mbexia mbexai mbaeix mbaexi
mbaiex mbaixe mbaxie mbaxei mbiaex mbiaxe mbieax mbiexa mbixea mbixae mbxaie
mbxaei mbxiae mbxiea mbxeia mbxeai miebax miebxa mieabx mieaxb miexab miexba
mibeax mibexa mibaex mibaxe mibxae mibxea miabex miabxe miaebx miaexb miaxeb
miaxbe mixbae mixbea mixabe mixaeb mixeab mixeba mxebia mxebai mxeiba mxeiab
mxeaib mxeabi mxbeia mxbeai mxbiea mxbiae mxbaie mxbaei mxibea mxibae mxieba
mxieab mxiaeb mxiabe mxabie mxabei mxaibe mxaieb mxaeib mxaebi emabix emabxi
emaibx emaixb emaxib emaxbi embaix embaxi embiax embixa embxia embxai emibax
emibxa emiabx emiaxb emixab emixba emxbia emxbai emxiba emxiab emxaib emxabi
eambix eambxi eamibx eamixb eamxib eamxbi eabmix eabmxi eabimx eabixm eabxim
eabxmi eaibmx eaibxm eaimbx eaimxb eaixmb eaixbm eaxbim eaxbmi eaxibm eaximb
eaxmib eaxmbi ebamix ebamxi ebaimx ebaixm ebaxim ebaxmi ebmaix ebmaxi ebmiax
ebmixa ebmxia ebmxai ebimax ebimxa ebiamx ebiaxm ebixam ebixma ebxmia ebxmai
ebxima ebxiam ebxaim ebxami eiabmx eiabxm eiambx eiamxb eiaxmb eiaxbm eibamx
eibaxm eibmax eibmxa eibxma eibxam eimbax eimbxa eimabx eimaxb eimxab eimxba
eixbma eixbam eixmba eixmab eixamb eixabm exabim exabmi exaibm exaimb examib
exambi exbaim exbami exbiam exbima exbmia exbmai exibam exibma exiabm exiamb
eximab eximba exmbia exmbai exmiba exmiab exmaib exmabi bmeaix bmeaxi bmeiax
bmeixa bmexia bmexai bmaeix bmaexi bmaiex bmaixe bmaxie bmaxei bmiaex bmiaxe
bmieax bmiexa bmixea bmixae bmxaie bmxaei bmxiae bmxiea bmxeia bmxeai bemaix
bemaxi bemiax bemixa bemxia bemxai beamix beamxi beaimx beaixm beaxim beaxmi
beiamx beiaxm beimax beimxa beixma beixam bexaim bexami bexiam bexima bexmia
bexmai baemix baemxi baeimx baeixm baexim baexmi bameix bamexi bamiex bamixe
bamxie bamxei baimex baimxe baiemx baiexm baixem baixme baxmie baxmei baxime
baxiem baxeim baxemi bieamx bieaxm biemax biemxa biexma biexam biaemx biaexm
biamex biamxe biaxme biaxem bimaex bimaxe bimeax bimexa bimxea bimxae bixame
bixaem bixmae bixmea bixema bixeam bxeaim bxeami bxeiam bxeima bxemia bxemai
bxaeim bxaemi bxaiem bxaime bxamie bxamei bxiaem bxiame bxieam bxiema bximea
bximae bxmaie bxmaei bxmiae bxmiea bxmeia bxmeai imebax imebxa imeabx imeaxb
imexab imexba imbeax imbexa imbaex imbaxe imbxae imbxea imabex imabxe imaebx
imaexb imaxeb imaxbe imxbae imxbea imxabe imxaeb imxeab imxeba iembax iembxa
iemabx iemaxb iemxab iemxba iebmax iebmxa iebamx iebaxm iebxam iebxma ieabmx
ieabxm ieambx ieamxb ieaxmb ieaxbm iexbam iexbma iexabm iexamb iexmab iexmba
ibemax ibemxa ibeamx ibeaxm ibexam ibexma ibmeax ibmexa ibmaex ibmaxe ibmxae
ibmxea ibamex ibamxe ibaemx ibaexm ibaxem ibaxme ibxmae ibxmea ibxame ibxaem
ibxeam ibxema iaebmx iaebxm iaembx iaemxb iaexmb iaexbm iabemx iabexm iabmex
iabmxe iabxme iabxem iambex iambxe iamebx iamexb iamxeb iamxbe iaxbme iaxbem
iaxmbe iaxmeb iaxemb iaxebm ixebam ixebma ixeabm ixeamb ixemab ixemba ixbeam
ixbema ixbaem ixbame ixbmae ixbmea ixabem ixabme ixaebm ixaemb ixameb ixambe
ixmbae ixmbea ixmabe ixmaeb ixmeab ixmeba xmebia xmebai xmeiba xmeiab xmeaib
xmeabi xmbeia xmbeai xmbiea xmbiae xmbaie xmbaei xmibea xmibae xmieba xmieab
xmiaeb xmiabe xmabie xmabei xmaibe xmaieb xmaeib xmaebi xembia xembai xemiba
xemiab xemaib xemabi xebmia xebmai xebima xebiam xebaim xebami xeibma xeibam
xeimba xeimab xeiamb xeiabm xeabim xeabmi xeaibm xeaimb xeamib xeambi xbemia
xbemai xbeima xbeiam xbeaim xbeami xbmeia xbmeai xbmiea xbmiae xbmaie xbmaei
xbimea xbimae xbiema xbieam xbiaem xbiame xbamie xbamei xbaime xbaiem xbaeim
xbaemi xiebma xiebam xiemba xiemab xieamb xieabm xibema xibeam xibmea xibmae
xibame xibaem ximbea ximbae ximeba ximeab ximaeb ximabe xiabme xiabem xiambe
xiameb xiaemb xiaebm xaebim xaebmi xaeibm xaeimb xaemib xaembi xabeim xabemi
xabiem xabime xabmie xabmei xaibem xaibme xaiebm xaiemb xaimeb xaimbe xambie
xambei xamibe xamieb xameib xamebi

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

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