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: sickel
cipher variations:
tjdlfm ukemgn vlfnho wmgoip xnhpjq
yoiqkr zpjrls aqksmt brltnu csmuov
dtnvpw euowqx fvpxry gwqysz hxrzta
iysaub jztbvc kaucwd lbvdxe mcweyf
ndxfzg oeygah pfzhbi qgaicj rhbjdk

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: sickel
Cipher: hrxpvo

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: sickel

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: sickel
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: sickel
Cipher: fvpxry

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: sickel
Cipher: 344231525113

Extended Methods:
Method #1

Plaintext: sickel
method variations:

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

Read more ...
Method #3

Plaintext: sickel
method variations:
tmvwan mvwant vwantm
wantmv antmvw ntmvwa

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: sickel

all 720 cipher variations:
sickel sickle sicekl sicelk siclek siclke sikcel sikcle sikecl sikelc siklec
siklce siekcl sieklc sieckl sieclk sielck sielkc silkec silkce silekc sileck
silcek silcke scikel scikle sciekl scielk scilek scilke sckiel sckile sckeil
sckeli scklei scklie scekil scekli sceikl sceilk scelik scelki sclkei sclkie
scleki scleik scliek sclike skciel skcile skceil skceli skclei skclie skicel
skicle skiecl skielc skilec skilce skeicl skeilc skecil skecli skelci skelic
skliec sklice skleic skleci sklcei sklcie seckil seckli secikl secilk seclik
seclki sekcil sekcli sekicl sekilc seklic seklci seikcl seiklc seickl seiclk
seilck seilkc selkic selkci selikc selick selcik selcki slckei slckie slceki
slceik slciek slcike slkcei slkcie slkeci slkeic slkiec slkice slekci slekic
slecki slecik sleick sleikc slikec slikce sliekc slieck slicek slicke isckel
isckle iscekl iscelk isclek isclke iskcel iskcle iskecl iskelc isklec isklce
isekcl iseklc iseckl iseclk iselck iselkc islkec islkce islekc isleck islcek
islcke icskel icskle icsekl icselk icslek icslke icksel icksle ickesl ickels
ickles icklse iceksl icekls iceskl iceslk icelsk icelks iclkes iclkse icleks
iclesk iclsek iclske ikcsel ikcsle ikcesl ikcels ikcles ikclse ikscel ikscle
iksecl ikselc ikslec ikslce ikescl ikeslc ikecsl ikecls ikelcs ikelsc iklsec
iklsce iklesc iklecs iklces iklcse iecksl ieckls iecskl iecslk ieclsk ieclks
iekcsl iekcls iekscl iekslc ieklsc ieklcs ieskcl iesklc iesckl iesclk ieslck
ieslkc ielksc ielkcs ielskc ielsck ielcsk ielcks ilckes ilckse ilceks ilcesk
ilcsek ilcske ilkces ilkcse ilkecs ilkesc ilksec ilksce ilekcs ileksc ilecks
ilecsk ilesck ileskc ilskec ilskce ilsekc ilseck ilscek ilscke ciskel ciskle
cisekl ciselk cislek cislke ciksel ciksle cikesl cikels cikles ciklse cieksl
ciekls cieskl cieslk cielsk cielks cilkes cilkse cileks cilesk cilsek cilske
csikel csikle csiekl csielk csilek csilke cskiel cskile cskeil cskeli csklei
csklie csekil csekli cseikl cseilk cselik cselki cslkei cslkie csleki csleik
csliek cslike cksiel cksile ckseil ckseli ckslei ckslie ckisel ckisle ckiesl
ckiels ckiles ckilse ckeisl ckeils ckesil ckesli ckelsi ckelis cklies cklise
ckleis cklesi cklsei cklsie ceskil ceskli cesikl cesilk ceslik ceslki ceksil
ceksli cekisl cekils ceklis ceklsi ceiksl ceikls ceiskl ceislk ceilsk ceilks
celkis celksi celiks celisk celsik celski clskei clskie clseki clseik clsiek
clsike clksei clksie clkesi clkeis clkies clkise cleksi clekis cleski clesik
cleisk cleiks clikes clikse clieks cliesk clisek cliske kicsel kicsle kicesl
kicels kicles kiclse kiscel kiscle kisecl kiselc kislec kislce kiescl kieslc
kiecsl kiecls kielcs kielsc kilsec kilsce kilesc kilecs kilces kilcse kcisel
kcisle kciesl kciels kciles kcilse kcsiel kcsile kcseil kcseli kcslei kcslie
kcesil kcesli kceisl kceils kcelis kcelsi kclsei kclsie kclesi kcleis kclies
kclise ksciel kscile ksceil ksceli ksclei ksclie ksicel ksicle ksiecl ksielc
ksilec ksilce kseicl kseilc ksecil ksecli kselci kselic ksliec kslice ksleic
ksleci kslcei kslcie kecsil kecsli kecisl kecils keclis keclsi kescil kescli
kesicl kesilc keslic keslci keiscl keislc keicsl keicls keilcs keilsc kelsic
kelsci kelisc kelics kelcis kelcsi klcsei klcsie klcesi klceis klcies klcise
klscei klscie klseci klseic klsiec klsice klesci klesic klecsi klecis kleics
kleisc klisec klisce kliesc kliecs klices klicse eicksl eickls eicskl eicslk
eiclsk eiclks eikcsl eikcls eikscl eikslc eiklsc eiklcs eiskcl eisklc eisckl
eisclk eislck eislkc eilksc eilkcs eilskc eilsck eilcsk eilcks eciksl ecikls
eciskl ecislk ecilsk ecilks eckisl eckils ecksil ecksli ecklsi ecklis ecskil
ecskli ecsikl ecsilk ecslik ecslki eclksi eclkis eclski eclsik eclisk ecliks
ekcisl ekcils ekcsil ekcsli ekclsi ekclis ekicsl ekicls ekiscl ekislc ekilsc
ekilcs eksicl eksilc ekscil ekscli ekslci ekslic eklisc eklics eklsic eklsci
eklcsi eklcis esckil esckli escikl escilk esclik esclki eskcil eskcli eskicl
eskilc esklic esklci esikcl esiklc esickl esiclk esilck esilkc eslkic eslkci
eslikc eslick eslcik eslcki elcksi elckis elcski elcsik elcisk elciks elkcsi
elkcis elksci elksic elkisc elkics elskci elskic elscki elscik elsick elsikc
eliksc elikcs eliskc elisck elicsk elicks lickes lickse liceks licesk licsek
licske likces likcse likecs likesc liksec liksce liekcs lieksc liecks liecsk
liesck lieskc liskec liskce lisekc liseck liscek liscke lcikes lcikse lcieks
lciesk lcisek lciske lckies lckise lckeis lckesi lcksei lcksie lcekis lceksi
lceiks lceisk lcesik lceski lcskei lcskie lcseki lcseik lcsiek lcsike lkcies
lkcise lkceis lkcesi lkcsei lkcsie lkices lkicse lkiecs lkiesc lkisec lkisce
lkeics lkeisc lkecis lkecsi lkesci lkesic lksiec lksice lkseic lkseci lkscei
lkscie leckis lecksi leciks lecisk lecsik lecski lekcis lekcsi lekics lekisc
leksic leksci leikcs leiksc leicks leicsk leisck leiskc leskic leskci lesikc
lesick lescik lescki lsckei lsckie lsceki lsceik lsciek lscike lskcei lskcie
lskeci lskeic lskiec lskice lsekci lsekic lsecki lsecik lseick lseikc lsikec
lsikce lsiekc lsieck lsicek lsicke

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

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