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: belkin
cipher variations:
cfmljo dgnmkp ehonlq fipomr gjqpns
hkrqot ilsrpu jmtsqv knutrw lovusx
mpwvty nqxwuz oryxva pszywb qtazxc
rubayd svcbze twdcaf uxedbg vyfech
wzgfdi xahgej ybihfk zcjigl adkjhm

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: belkin
Cipher: yvoprm

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: belkin

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: belkin
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: belkin
Cipher: oryxva

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: belkin
Cipher: 215113524233

Extended Methods:
Method #1

Plaintext: belkin
method variations:

Method #2
Bifid cipher
The message is converted to its coordinates in the usual manner, but they are written vertically beneath:
b e l k i n 
2 5 1 5 4 3 
1 1 3 2 2 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: belkin
Cipher: wvoahm

Read more ...
Method #3

Plaintext: belkin
method variations:
vaxrmh axrmhv xrmhva
rmhvax mhvaxr hvaxrm

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: belkin

all 720 cipher variations:
belkin belkni belikn belink belnik belnki beklin beklni bekiln bekinl beknil
beknli beikln beiknl beilkn beilnk beinlk beinkl benkil benkli benikl benilk
benlik benlki blekin blekni bleikn bleink blenik blenki blkein blkeni blkien
blkine blknie blknei bliken blikne bliekn blienk blinek blinke blnkie blnkei
blnike blniek blneik blneki bklein bkleni bklien bkline bklnie bklnei bkelin
bkelni bkeiln bkeinl bkenil bkenli bkieln bkienl bkilen bkilne bkinle bkinel
bkneil bkneli bkniel bknile bknlie bknlei bilken bilkne bilekn bilenk bilnek
bilnke biklen biklne bikeln bikenl biknel biknle biekln bieknl bielkn bielnk
bienlk bienkl binkel binkle binekl binelk binlek binlke bnlkie bnlkei bnlike
bnliek bnleik bnleki bnklie bnklei bnkile bnkiel bnkeil bnkeli bnikle bnikel
bnilke bnilek bnielk bniekl bnekil bnekli bneikl bneilk bnelik bnelki eblkin
eblkni eblikn eblink eblnik eblnki ebklin ebklni ebkiln ebkinl ebknil ebknli
ebikln ebiknl ebilkn ebilnk ebinlk ebinkl ebnkil ebnkli ebnikl ebnilk ebnlik
ebnlki elbkin elbkni elbikn elbink elbnik elbnki elkbin elkbni elkibn elkinb
elknib elknbi elikbn eliknb elibkn elibnk elinbk elinkb elnkib elnkbi elnikb
elnibk elnbik elnbki eklbin eklbni eklibn eklinb eklnib eklnbi ekblin ekblni
ekbiln ekbinl ekbnil ekbnli ekibln ekibnl ekilbn ekilnb ekinlb ekinbl eknbil
eknbli eknibl eknilb eknlib eknlbi eilkbn eilknb eilbkn eilbnk eilnbk eilnkb
eiklbn eiklnb eikbln eikbnl eiknbl eiknlb eibkln eibknl eiblkn eiblnk eibnlk
eibnkl einkbl einklb einbkl einblk einlbk einlkb enlkib enlkbi enlikb enlibk
enlbik enlbki enklib enklbi enkilb enkibl enkbil enkbli eniklb enikbl enilkb
enilbk eniblk enibkl enbkil enbkli enbikl enbilk enblik enblki lebkin lebkni
lebikn lebink lebnik lebnki lekbin lekbni lekibn lekinb leknib leknbi leikbn
leiknb leibkn leibnk leinbk leinkb lenkib lenkbi lenikb lenibk lenbik lenbki
lbekin lbekni lbeikn lbeink lbenik lbenki lbkein lbkeni lbkien lbkine lbknie
lbknei lbiken lbikne lbiekn lbienk lbinek lbinke lbnkie lbnkei lbnike lbniek
lbneik lbneki lkbein lkbeni lkbien lkbine lkbnie lkbnei lkebin lkebni lkeibn
lkeinb lkenib lkenbi lkiebn lkienb lkiben lkibne lkinbe lkineb lkneib lknebi
lknieb lknibe lknbie lknbei libken libkne libekn libenk libnek libnke likben
likbne likebn likenb likneb liknbe liekbn lieknb liebkn liebnk lienbk lienkb
linkeb linkbe linekb linebk linbek linbke lnbkie lnbkei lnbike lnbiek lnbeik
lnbeki lnkbie lnkbei lnkibe lnkieb lnkeib lnkebi lnikbe lnikeb lnibke lnibek
lniebk lniekb lnekib lnekbi lneikb lneibk lnebik lnebki kelbin kelbni kelibn
kelinb kelnib kelnbi keblin keblni kebiln kebinl kebnil kebnli keibln keibnl
keilbn keilnb keinlb keinbl kenbil kenbli kenibl kenilb kenlib kenlbi klebin
klebni kleibn kleinb klenib klenbi klbein klbeni klbien klbine klbnie klbnei
kliben klibne kliebn klienb klineb klinbe klnbie klnbei klnibe klnieb klneib
klnebi kblein kbleni kblien kbline kblnie kblnei kbelin kbelni kbeiln kbeinl
kbenil kbenli kbieln kbienl kbilen kbilne kbinle kbinel kbneil kbneli kbniel
kbnile kbnlie kbnlei kilben kilbne kilebn kilenb kilneb kilnbe kiblen kiblne
kibeln kibenl kibnel kibnle kiebln kiebnl kielbn kielnb kienlb kienbl kinbel
kinble kinebl kinelb kinleb kinlbe knlbie knlbei knlibe knlieb knleib knlebi
knblie knblei knbile knbiel knbeil knbeli knible knibel knilbe knileb knielb
kniebl knebil knebli kneibl kneilb knelib knelbi ielkbn ielknb ielbkn ielbnk
ielnbk ielnkb ieklbn ieklnb iekbln iekbnl ieknbl ieknlb iebkln iebknl ieblkn
ieblnk iebnlk iebnkl ienkbl ienklb ienbkl ienblk ienlbk ienlkb ilekbn ileknb
ilebkn ilebnk ilenbk ilenkb ilkebn ilkenb ilkben ilkbne ilknbe ilkneb ilbken
ilbkne ilbekn ilbenk ilbnek ilbnke ilnkbe ilnkeb ilnbke ilnbek ilnebk ilnekb
iklebn iklenb iklben iklbne iklnbe iklneb ikelbn ikelnb ikebln ikebnl ikenbl
ikenlb ikbeln ikbenl ikblen ikblne ikbnle ikbnel iknebl iknelb iknbel iknble
iknlbe iknleb iblken iblkne iblekn iblenk iblnek iblnke ibklen ibklne ibkeln
ibkenl ibknel ibknle ibekln ibeknl ibelkn ibelnk ibenlk ibenkl ibnkel ibnkle
ibnekl ibnelk ibnlek ibnlke inlkbe inlkeb inlbke inlbek inlebk inlekb inklbe
inkleb inkble inkbel inkebl inkelb inbkle inbkel inblke inblek inbelk inbekl
inekbl ineklb inebkl ineblk inelbk inelkb nelkib nelkbi nelikb nelibk nelbik
nelbki neklib neklbi nekilb nekibl nekbil nekbli neiklb neikbl neilkb neilbk
neiblk neibkl nebkil nebkli nebikl nebilk neblik neblki nlekib nlekbi nleikb
nleibk nlebik nlebki nlkeib nlkebi nlkieb nlkibe nlkbie nlkbei nlikeb nlikbe
nliekb nliebk nlibek nlibke nlbkie nlbkei nlbike nlbiek nlbeik nlbeki nkleib
nklebi nklieb nklibe nklbie nklbei nkelib nkelbi nkeilb nkeibl nkebil nkebli
nkielb nkiebl nkileb nkilbe nkible nkibel nkbeil nkbeli nkbiel nkbile nkblie
nkblei nilkeb nilkbe nilekb nilebk nilbek nilbke nikleb niklbe nikelb nikebl
nikbel nikble nieklb niekbl nielkb nielbk nieblk niebkl nibkel nibkle nibekl
nibelk niblek niblke nblkie nblkei nblike nbliek nbleik nbleki nbklie nbklei
nbkile nbkiel nbkeil nbkeli nbikle nbikel nbilke nbilek nbielk nbiekl nbekil
nbekli nbeikl nbeilk nbelik nbelki

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

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