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: italos
cipher variations:
jubmpt kvcnqu lwdorv mxepsw nyfqtx
ozgruy pahsvz qbitwa rcjuxb sdkvyc
telwzd ufmxae vgnybf whozcg xipadh
yjqbei zkrcfj alsdgk bmtehl cnufim
dovgjn epwhko fqxilp gryjmq hszknr

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: italos
Cipher: rgzolh

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: italos

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: italos
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: italos
Cipher: vgnybf

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: italos
Cipher: 424411134334

Extended Methods:
Method #1

Plaintext: italos
method variations:

Method #2
Bifid cipher
The message is converted to its coordinates in the usual manner, but they are written vertically beneath:
i t a l o s 
4 4 1 1 4 3 
2 4 1 3 3 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: italos
Cipher: taorls

Read more ...
Method #3

Plaintext: italos
method variations:
rdasnt dasntr asntrd
sntrda ntrdas trdasn

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: italos

all 720 cipher variations:
italos italso itaols itaosl itasol itaslo itlaos itlaso itloas itlosa itlsoa
itlsao itolas itolsa itoals itoasl itosal itosla itsloa itslao itsola itsoal
itsaol itsalo iatlos iatlso iatols iatosl iatsol iatslo ialtos ialtso ialots
ialost ialsot ialsto iaolts iaolst iaotls iaotsl iaostl iaoslt iaslot iaslto
iasolt iasotl iastol iastlo ilatos ilatso ilaots ilaost ilasot ilasto iltaos
iltaso iltoas iltosa iltsoa iltsao ilotas ilotsa iloats iloast ilosat ilosta
ilstoa ilstao ilsota ilsoat ilsaot ilsato ioalts ioalst ioatls ioatsl ioastl
ioaslt iolats iolast ioltas ioltsa iolsta iolsat iotlas iotlsa iotals iotasl
iotsal iotsla ioslta ioslat iostla iostal iosatl iosalt isalot isalto isaolt
isaotl isatol isatlo islaot islato isloat islota isltoa isltao isolat isolta
isoalt isoatl isotal isotla istloa istlao istola istoal istaol istalo tialos
tialso tiaols tiaosl tiasol tiaslo tilaos tilaso tiloas tilosa tilsoa tilsao
tiolas tiolsa tioals tioasl tiosal tiosla tisloa tislao tisola tisoal tisaol
tisalo tailos tailso taiols taiosl taisol taislo talios taliso talois talosi
talsoi talsio taolis taolsi taoils taoisl taosil taosli tasloi taslio tasoli
tasoil tasiol tasilo tlaios tlaiso tlaois tlaosi tlasoi tlasio tliaos tliaso
tlioas tliosa tlisoa tlisao tloias tloisa tloais tloasi tlosai tlosia tlsioa
tlsiao tlsoia tlsoai tlsaoi tlsaio toalis toalsi toails toaisl toasil toasli
tolais tolasi tolias tolisa tolsia tolsai toilas toilsa toials toiasl toisal
toisla toslia toslai tosila tosial tosail tosali tsaloi tsalio tsaoli tsaoil
tsaiol tsailo tslaoi tslaio tsloai tsloia tslioa tsliao tsolai tsolia tsoali
tsoail tsoial tsoila tsiloa tsilao tsiola tsioal tsiaol tsialo atilos atilso
atiols atiosl atisol atislo atlios atliso atlois atlosi atlsoi atlsio atolis
atolsi atoils atoisl atosil atosli atsloi atslio atsoli atsoil atsiol atsilo
aitlos aitlso aitols aitosl aitsol aitslo ailtos ailtso ailots ailost ailsot
ailsto aiolts aiolst aiotls aiotsl aiostl aioslt aislot aislto aisolt aisotl
aistol aistlo alitos alitso aliots aliost alisot alisto altios altiso altois
altosi altsoi altsio alotis alotsi aloits aloist alosit alosti alstoi alstio
alsoti alsoit alsiot alsito aoilts aoilst aoitls aoitsl aoistl aoislt aolits
aolist aoltis aoltsi aolsti aolsit aotlis aotlsi aotils aotisl aotsil aotsli
aoslti aoslit aostli aostil aositl aosilt asilot asilto asiolt asiotl asitol
asitlo asliot aslito asloit asloti asltoi asltio asolit asolti asoilt asoitl
asotil asotli astloi astlio astoli astoil astiol astilo ltaios ltaiso ltaois
ltaosi ltasoi ltasio ltiaos ltiaso ltioas ltiosa ltisoa ltisao ltoias ltoisa
ltoais ltoasi ltosai ltosia ltsioa ltsiao ltsoia ltsoai ltsaoi ltsaio latios
latiso latois latosi latsoi latsio laitos laitso laiots laiost laisot laisto
laoits laoist laotis laotsi laosti laosit lasiot lasito lasoit lasoti lastoi
lastio liatos liatso liaots liaost liasot liasto litaos litaso litoas litosa
litsoa litsao liotas liotsa lioats lioast liosat liosta listoa listao lisota
lisoat lisaot lisato loaits loaist loatis loatsi loasti loasit loiats loiast
loitas loitsa loista loisat lotias lotisa lotais lotasi lotsai lotsia losita
losiat lostia lostai losati losait lsaiot lsaito lsaoit lsaoti lsatoi lsatio
lsiaot lsiato lsioat lsiota lsitoa lsitao lsoiat lsoita lsoait lsoati lsotai
lsotia lstioa lstiao lstoia lstoai lstaoi lstaio otalis otalsi otails otaisl
otasil otasli otlais otlasi otlias otlisa otlsia otlsai otilas otilsa otials
otiasl otisal otisla otslia otslai otsila otsial otsail otsali oatlis oatlsi
oatils oatisl oatsil oatsli oaltis oaltsi oalits oalist oalsit oalsti oailts
oailst oaitls oaitsl oaistl oaislt oaslit oaslti oasilt oasitl oastil oastli
olatis olatsi olaits olaist olasit olasti oltais oltasi oltias oltisa oltsia
oltsai olitas olitsa oliats oliast olisat olista olstia olstai olsita olsiat
olsait olsati oialts oialst oiatls oiatsl oiastl oiaslt oilats oilast oiltas
oiltsa oilsta oilsat oitlas oitlsa oitals oitasl oitsal oitsla oislta oislat
oistla oistal oisatl oisalt osalit osalti osailt osaitl osatil osatli oslait
oslati osliat oslita osltia osltai osilat osilta osialt osiatl osital ositla
ostlia ostlai ostila ostial ostail ostali staloi stalio staoli staoil staiol
stailo stlaoi stlaio stloai stloia stlioa stliao stolai stolia stoali stoail
stoial stoila stiloa stilao stiola stioal stiaol stialo satloi satlio satoli
satoil satiol satilo saltoi saltio saloti saloit saliot salito saolti saolit
saotli saotil saoitl saoilt sailot sailto saiolt saiotl saitol saitlo slatoi
slatio slaoti slaoit slaiot slaito sltaoi sltaio sltoai sltoia sltioa sltiao
slotai slotia sloati sloait sloiat sloita slitoa slitao sliota slioat sliaot
sliato soalti soalit soatli soatil soaitl soailt solati solait soltai soltia
solita soliat sotlai sotlia sotali sotail sotial sotila soilta soilat soitla
soital soiatl soialt sialot sialto siaolt siaotl siatol siatlo silaot silato
siloat silota siltoa siltao siolat siolta sioalt sioatl siotal siotla sitloa
sitlao sitola sitoal sitaol sitalo

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

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