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: lometa
cipher variations:
mpnfub nqogvc orphwd psqixe qtrjyf
ruskzg svtlah twumbi uxvncj vywodk
wzxpel xayqfm ybzrgn zcasho adbtip
becujq cfdvkr dgewls ehfxmt figynu
gjhzov hkiapw iljbqx jmkcry knldsz

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: lometa
Cipher: olnvgz

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: lometa

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: lometa
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: lometa
Cipher: ybzrgn

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: lometa
Cipher: 134323514411

Extended Methods:
Method #1

Plaintext: lometa
method variations:

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

Read more ...
Method #3

Plaintext: lometa
method variations:
shxqda hxqdas xqdash
qdashx dashxq ashxqd

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: lometa

all 720 cipher variations:
lometa lomeat lomtea lomtae lomate lomaet loemta loemat loetma loetam loeatm
loeamt lotema loteam lotmea lotmae lotame lotaem loaetm loaemt loatem loatme
loamte loamet lmoeta lmoeat lmotea lmotae lmoate lmoaet lmeota lmeoat lmetoa
lmetao lmeato lmeaot lmteoa lmteao lmtoea lmtoae lmtaoe lmtaeo lmaeto lmaeot
lmateo lmatoe lmaote lmaoet lemota lemoat lemtoa lemtao lemato lemaot leomta
leomat leotma leotam leoatm leoamt letoma letoam letmoa letmao letamo letaom
leaotm leaomt leatom leatmo leamto leamot ltmeoa ltmeao ltmoea ltmoae ltmaoe
ltmaeo ltemoa ltemao lteoma lteoam lteaom lteamo ltoema ltoeam ltomea ltomae
ltoame ltoaem ltaeom ltaemo ltaoem ltaome ltamoe ltameo lameto lameot lamteo
lamtoe lamote lamoet laemto laemot laetmo laetom laeotm laeomt latemo lateom
latmeo latmoe latome latoem laoetm laoemt laotem laotme laomte laomet olmeta
olmeat olmtea olmtae olmate olmaet olemta olemat oletma oletam oleatm oleamt
oltema olteam oltmea oltmae oltame oltaem olaetm olaemt olatem olatme olamte
olamet omleta omleat omltea omltae omlate omlaet omelta omelat ometla ometal
omeatl omealt omtela omteal omtlea omtlae omtale omtael omaetl omaelt omatel
omatle omalte omalet oemlta oemlat oemtla oemtal oematl oemalt oelmta oelmat
oeltma oeltam oelatm oelamt oetlma oetlam oetmla oetmal oetaml oetalm oealtm
oealmt oeatlm oeatml oeamtl oeamlt otmela otmeal otmlea otmlae otmale otmael
otemla otemal otelma otelam otealm oteaml otlema otleam otlmea otlmae otlame
otlaem otaelm otaeml otalem otalme otamle otamel oametl oamelt oamtel oamtle
oamlte oamlet oaemtl oaemlt oaetml oaetlm oaeltm oaelmt oateml oatelm oatmel
oatmle oatlme oatlem oaletm oalemt oaltem oaltme oalmte oalmet moleta moleat
moltea moltae molate molaet moelta moelat moetla moetal moeatl moealt motela
moteal motlea motlae motale motael moaetl moaelt moatel moatle moalte moalet
mloeta mloeat mlotea mlotae mloate mloaet mleota mleoat mletoa mletao mleato
mleaot mlteoa mlteao mltoea mltoae mltaoe mltaeo mlaeto mlaeot mlateo mlatoe
mlaote mlaoet melota meloat meltoa meltao melato melaot meolta meolat meotla
meotal meoatl meoalt metola metoal metloa metlao metalo metaol meaotl meaolt
meatol meatlo mealto mealot mtleoa mtleao mtloea mtloae mtlaoe mtlaeo mteloa
mtelao mteola mteoal mteaol mtealo mtoela mtoeal mtolea mtolae mtoale mtoael
mtaeol mtaelo mtaoel mtaole mtaloe mtaleo maleto maleot malteo maltoe malote
maloet maelto maelot maetlo maetol maeotl maeolt matelo mateol matleo matloe
matole matoel maoetl maoelt maotel maotle maolte maolet eomlta eomlat eomtla
eomtal eomatl eomalt eolmta eolmat eoltma eoltam eolatm eolamt eotlma eotlam
eotmla eotmal eotaml eotalm eoaltm eoalmt eoatlm eoatml eoamtl eoamlt emolta
emolat emotla emotal emoatl emoalt emlota emloat emltoa emltao emlato emlaot
emtloa emtlao emtola emtoal emtaol emtalo emalto emalot ematlo ematol emaotl
emaolt elmota elmoat elmtoa elmtao elmato elmaot elomta elomat elotma elotam
eloatm eloamt eltoma eltoam eltmoa eltmao eltamo eltaom elaotm elaomt elatom
elatmo elamto elamot etmloa etmlao etmola etmoal etmaol etmalo etlmoa etlmao
etloma etloam etlaom etlamo etolma etolam etomla etomal etoaml etoalm etalom
etalmo etaolm etaoml etamol etamlo eamlto eamlot eamtlo eamtol eamotl eamolt
ealmto ealmot ealtmo ealtom ealotm ealomt eatlmo eatlom eatmlo eatmol eatoml
eatolm eaoltm eaolmt eaotlm eaotml eaomtl eaomlt tomela tomeal tomlea tomlae
tomale tomael toemla toemal toelma toelam toealm toeaml tolema toleam tolmea
tolmae tolame tolaem toaelm toaeml toalem toalme toamle toamel tmoela tmoeal
tmolea tmolae tmoale tmoael tmeola tmeoal tmeloa tmelao tmealo tmeaol tmleoa
tmleao tmloea tmloae tmlaoe tmlaeo tmaelo tmaeol tmaleo tmaloe tmaole tmaoel
temola temoal temloa temlao temalo temaol teomla teomal teolma teolam teoalm
teoaml teloma teloam telmoa telmao telamo telaom teaolm teaoml tealom tealmo
teamlo teamol tlmeoa tlmeao tlmoea tlmoae tlmaoe tlmaeo tlemoa tlemao tleoma
tleoam tleaom tleamo tloema tloeam tlomea tlomae tloame tloaem tlaeom tlaemo
tlaoem tlaome tlamoe tlameo tamelo tameol tamleo tamloe tamole tamoel taemlo
taemol taelmo taelom taeolm taeoml talemo taleom talmeo talmoe talome taloem
taoelm taoeml taolem taolme taomle taomel aometl aomelt aomtel aomtle aomlte
aomlet aoemtl aoemlt aoetml aoetlm aoeltm aoelmt aoteml aotelm aotmel aotmle
aotlme aotlem aoletm aolemt aoltem aoltme aolmte aolmet amoetl amoelt amotel
amotle amolte amolet ameotl ameolt ametol ametlo amelto amelot amteol amtelo
amtoel amtole amtloe amtleo amleto amleot amlteo amltoe amlote amloet aemotl
aemolt aemtol aemtlo aemlto aemlot aeomtl aeomlt aeotml aeotlm aeoltm aeolmt
aetoml aetolm aetmol aetmlo aetlmo aetlom aelotm aelomt aeltom aeltmo aelmto
aelmot atmeol atmelo atmoel atmole atmloe atmleo atemol atemlo ateoml ateolm
atelom atelmo atoeml atoelm atomel atomle atolme atolem atleom atlemo atloem
atlome atlmoe atlmeo almeto almeot almteo almtoe almote almoet alemto alemot
aletmo aletom aleotm aleomt altemo alteom altmeo altmoe altome altoem aloetm
aloemt alotem alotme alomte alomet

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

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