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: wreath
cipher variations:
xsfbui ytgcvj zuhdwk aviexl bwjfym
cxkgzn dylhao ezmibp fanjcq gbokdr
hcples idqmft jerngu kfsohv lgtpiw
mhuqjx nivrky ojwslz pkxtma qlyunb
rmzvoc snawpd tobxqe upcyrf vqdzsg

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: wreath
Cipher: divzgs

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: wreath

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: wreath
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: wreath
Cipher: jerngu

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: wreath
Cipher: 252451114432

Extended Methods:
Method #1

Plaintext: wreath
method variations:

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

Read more ...
Method #3

Plaintext: wreath
method variations:
kyaqog yaqogk aqogky
qogkya ogkyaq gkyaqo

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: wreath

all 720 cipher variations:
wreath wreaht wretah wretha wrehta wrehat wraeth wraeht wrateh wrathe wrahte
wrahet wrtaeh wrtahe wrteah wrteha wrthea wrthae wrhate wrhaet wrhtae wrhtea
wrheta wrheat werath weraht wertah wertha werhta werhat wearth wearht weatrh
weathr weahtr weahrt wetarh wetahr wetrah wetrha wethra wethar wehatr wehart
wehtar wehtra wehrta wehrat waerth waerht waetrh waethr waehtr waehrt wareth
wareht warteh warthe warhte warhet watreh watrhe waterh watehr wather wathre
wahrte wahret wahtre wahter wahetr wahert wtearh wteahr wterah wterha wtehra
wtehar wtaerh wtaehr wtareh wtarhe wtahre wtaher wtraeh wtrahe wtreah wtreha
wtrhea wtrhae wthare wthaer wthrae wthrea wthera wthear wheatr wheart whetar
whetra wherta wherat whaetr whaert whater whatre wharte wharet whtaer whtare
whtear whtera whtrea whtrae whrate whraet whrtae whrtea whreta whreat rweath
rweaht rwetah rwetha rwehta rwehat rwaeth rwaeht rwateh rwathe rwahte rwahet
rwtaeh rwtahe rwteah rwteha rwthea rwthae rwhate rwhaet rwhtae rwhtea rwheta
rwheat rewath rewaht rewtah rewtha rewhta rewhat reawth reawht reatwh reathw
reahtw reahwt retawh retahw retwah retwha rethwa rethaw rehatw rehawt rehtaw
rehtwa rehwta rehwat raewth raewht raetwh raethw raehtw raehwt raweth raweht
rawteh rawthe rawhte rawhet ratweh ratwhe ratewh ratehw rathew rathwe rahwte
rahwet rahtwe rahtew rahetw rahewt rteawh rteahw rtewah rtewha rtehwa rtehaw
rtaewh rtaehw rtaweh rtawhe rtahwe rtahew rtwaeh rtwahe rtweah rtweha rtwhea
rtwhae rthawe rthaew rthwae rthwea rthewa rtheaw rheatw rheawt rhetaw rhetwa
rhewta rhewat rhaetw rhaewt rhatew rhatwe rhawte rhawet rhtaew rhtawe rhteaw
rhtewa rhtwea rhtwae rhwate rhwaet rhwtae rhwtea rhweta rhweat erwath erwaht
erwtah erwtha erwhta erwhat erawth erawht eratwh erathw erahtw erahwt ertawh
ertahw ertwah ertwha erthwa erthaw erhatw erhawt erhtaw erhtwa erhwta erhwat
ewrath ewraht ewrtah ewrtha ewrhta ewrhat ewarth ewarht ewatrh ewathr ewahtr
ewahrt ewtarh ewtahr ewtrah ewtrha ewthra ewthar ewhatr ewhart ewhtar ewhtra
ewhrta ewhrat eawrth eawrht eawtrh eawthr eawhtr eawhrt earwth earwht eartwh
earthw earhtw earhwt eatrwh eatrhw eatwrh eatwhr eathwr eathrw eahrtw eahrwt
eahtrw eahtwr eahwtr eahwrt etwarh etwahr etwrah etwrha etwhra etwhar etawrh
etawhr etarwh etarhw etahrw etahwr etrawh etrahw etrwah etrwha etrhwa etrhaw
etharw ethawr ethraw ethrwa ethwra ethwar ehwatr ehwart ehwtar ehwtra ehwrta
ehwrat ehawtr ehawrt ehatwr ehatrw ehartw eharwt ehtawr ehtarw ehtwar ehtwra
ehtrwa ehtraw ehratw ehrawt ehrtaw ehrtwa ehrwta ehrwat arewth arewht aretwh
arethw arehtw arehwt arweth arweht arwteh arwthe arwhte arwhet artweh artwhe
artewh artehw arthew arthwe arhwte arhwet arhtwe arhtew arhetw arhewt aerwth
aerwht aertwh aerthw aerhtw aerhwt aewrth aewrht aewtrh aewthr aewhtr aewhrt
aetwrh aetwhr aetrwh aetrhw aethrw aethwr aehwtr aehwrt aehtwr aehtrw aehrtw
aehrwt awerth awerht awetrh awethr awehtr awehrt awreth awreht awrteh awrthe
awrhte awrhet awtreh awtrhe awterh awtehr awther awthre awhrte awhret awhtre
awhter awhetr awhert atewrh atewhr aterwh aterhw atehrw atehwr atwerh atwehr
atwreh atwrhe atwhre atwher atrweh atrwhe atrewh atrehw atrhew atrhwe athwre
athwer athrwe athrew atherw athewr ahewtr ahewrt ahetwr ahetrw ahertw aherwt
ahwetr ahwert ahwter ahwtre ahwrte ahwret ahtwer ahtwre ahtewr ahterw ahtrew
ahtrwe ahrwte ahrwet ahrtwe ahrtew ahretw ahrewt treawh treahw trewah trewha
trehwa trehaw traewh traehw traweh trawhe trahwe trahew trwaeh trwahe trweah
trweha trwhea trwhae trhawe trhaew trhwae trhwea trhewa trheaw terawh terahw
terwah terwha terhwa terhaw tearwh tearhw teawrh teawhr teahwr teahrw tewarh
tewahr tewrah tewrha tewhra tewhar tehawr teharw tehwar tehwra tehrwa tehraw
taerwh taerhw taewrh taewhr taehwr taehrw tarewh tarehw tarweh tarwhe tarhwe
tarhew tawreh tawrhe tawerh tawehr tawher tawhre tahrwe tahrew tahwre tahwer
tahewr taherw twearh tweahr twerah twerha twehra twehar twaerh twaehr twareh
twarhe twahre twaher twraeh twrahe twreah twreha twrhea twrhae twhare twhaer
twhrae twhrea twhera twhear theawr thearw thewar thewra therwa theraw thaewr
thaerw thawer thawre tharwe tharew thwaer thware thwear thwera thwrea thwrae
thrawe thraew thrwae thrwea threwa threaw hreatw hreawt hretaw hretwa hrewta
hrewat hraetw hraewt hratew hratwe hrawte hrawet hrtaew hrtawe hrteaw hrtewa
hrtwea hrtwae hrwate hrwaet hrwtae hrwtea hrweta hrweat heratw herawt hertaw
hertwa herwta herwat heartw hearwt heatrw heatwr heawtr heawrt hetarw hetawr
hetraw hetrwa hetwra hetwar hewatr hewart hewtar hewtra hewrta hewrat haertw
haerwt haetrw haetwr haewtr haewrt haretw harewt hartew hartwe harwte harwet
hatrew hatrwe haterw hatewr hatwer hatwre hawrte hawret hawtre hawter hawetr
hawert htearw hteawr hteraw hterwa htewra htewar htaerw htaewr htarew htarwe
htawre htawer htraew htrawe htreaw htrewa htrwea htrwae htware htwaer htwrae
htwrea htwera htwear hweatr hweart hwetar hwetra hwerta hwerat hwaetr hwaert
hwater hwatre hwarte hwaret hwtaer hwtare hwtear hwtera hwtrea hwtrae hwrate
hwraet hwrtae hwrtea hwreta hwreat

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

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