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: ramies
cipher variations:
sbnjft tcokgu udplhv veqmiw wfrnjx
xgsoky yhtplz ziuqma ajvrnb bkwsoc
clxtpd dmyuqe enzvrf foawsg gpbxth
hqcyui irdzvj jseawk ktfbxl lugcym
mvhdzn nwieao oxjfbp pykgcq qzlhdr

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: ramies
Cipher: iznrvh

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: ramies

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: ramies
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: ramies
Cipher: enzvrf

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: ramies
Cipher: 241123425134

Extended Methods:
Method #1

Plaintext: ramies
method variations:

Method #2
Bifid cipher
The message is converted to its coordinates in the usual manner, but they are written vertically beneath:
r a m i e s 
2 1 2 4 5 3 
4 1 3 2 1 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: ramies
Cipher: brpdhq

Read more ...
Method #3

Plaintext: ramies
method variations:
dfswli fswlid swlidf
wlidfs lidfsw idfswl

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: ramies

all 720 cipher variations:
ramies ramise rameis ramesi ramsei ramsie raimes raimse raiems raiesm raisem
raisme raeims raeism raemis raemsi raesmi raesim rasiem rasime raseim rasemi
rasmei rasmie rmaies rmaise rmaeis rmaesi rmasei rmasie rmiaes rmiase rmieas
rmiesa rmisea rmisae rmeias rmeisa rmeais rmeasi rmesai rmesia rmsiea rmsiae
rmseia rmseai rmsaei rmsaie rimaes rimase rimeas rimesa rimsea rimsae riames
riamse riaems riaesm riasem riasme rieams rieasm riemas riemsa riesma riesam
risaem risame riseam risema rismea rismae remias remisa remais remasi remsai
remsia reimas reimsa reiams reiasm reisam reisma reaims reaism reamis reamsi
reasmi reasim resiam resima resaim resami resmai resmia rsmiea rsmiae rsmeia
rsmeai rsmaei rsmaie rsimea rsimae rsiema rsieam rsiaem rsiame rseima rseiam
rsemia rsemai rseami rseaim rsaiem rsaime rsaeim rsaemi rsamei rsamie armies
armise armeis armesi armsei armsie arimes arimse ariems ariesm arisem arisme
areims areism aremis aremsi aresmi aresim arsiem arsime arseim arsemi arsmei
arsmie amries amrise amreis amresi amrsei amrsie amires amirse amiers amiesr
amiser amisre ameirs ameisr ameris amersi amesri amesir amsier amsire amseir
amseri amsrei amsrie aimres aimrse aimers aimesr aimser aimsre airmes airmse
airems airesm airsem airsme aierms aiersm aiemrs aiemsr aiesmr aiesrm aisrem
aisrme aiserm aisemr aismer aismre aemirs aemisr aemris aemrsi aemsri aemsir
aeimrs aeimsr aeirms aeirsm aeisrm aeismr aerims aerism aermis aermsi aersmi
aersim aesirm aesimr aesrim aesrmi aesmri aesmir asmier asmire asmeir asmeri
asmrei asmrie asimer asimre asiemr asierm asirem asirme aseimr aseirm asemir
asemri asermi aserim asriem asrime asreim asremi asrmei asrmie maries marise
mareis maresi marsei marsie maires mairse maiers maiesr maiser maisre maeirs
maeisr maeris maersi maesri maesir masier masire maseir maseri masrei masrie
mraies mraise mraeis mraesi mrasei mrasie mriaes mriase mrieas mriesa mrisea
mrisae mreias mreisa mreais mreasi mresai mresia mrsiea mrsiae mrseia mrseai
mrsaei mrsaie miraes mirase mireas miresa mirsea mirsae miares miarse miaers
miaesr miaser miasre miears mieasr mieras miersa miesra miesar misaer misare
misear misera misrea misrae merias merisa merais merasi mersai mersia meiras
meirsa meiars meiasr meisar meisra meairs meaisr mearis mearsi measri measir
mesiar mesira mesair mesari mesrai mesria msriea msriae msreia msreai msraei
msraie msirea msirae msiera msiear msiaer msiare mseira mseiar mseria mserai
mseari mseair msaier msaire msaeir msaeri msarei msarie iamres iamrse iamers
iamesr iamser iamsre iarmes iarmse iarems iaresm iarsem iarsme iaerms iaersm
iaemrs iaemsr iaesmr iaesrm iasrem iasrme iaserm iasemr iasmer iasmre imares
imarse imaers imaesr imaser imasre imraes imrase imreas imresa imrsea imrsae
imeras imersa imears imeasr imesar imesra imsrea imsrae imsera imsear imsaer
imsare irmaes irmase irmeas irmesa irmsea irmsae irames iramse iraems iraesm
irasem irasme ireams ireasm iremas iremsa iresma iresam irsaem irsame irseam
irsema irsmea irsmae iemras iemrsa iemars iemasr iemsar iemsra iermas iermsa
ierams ierasm iersam iersma iearms iearsm ieamrs ieamsr ieasmr ieasrm iesram
iesrma iesarm iesamr iesmar iesmra ismrea ismrae ismera ismear ismaer ismare
isrmea isrmae isrema isream israem israme iserma iseram isemra isemar iseamr
isearm isarem isarme isaerm isaemr isamer isamre eamirs eamisr eamris eamrsi
eamsri eamsir eaimrs eaimsr eairms eairsm eaisrm eaismr earims earism earmis
earmsi earsmi earsim easirm easimr easrim easrmi easmri easmir emairs emaisr
emaris emarsi emasri emasir emiars emiasr emiras emirsa emisra emisar emrias
emrisa emrais emrasi emrsai emrsia emsira emsiar emsria emsrai emsari emsair
eimars eimasr eimras eimrsa eimsra eimsar eiamrs eiamsr eiarms eiarsm eiasrm
eiasmr eirams eirasm eirmas eirmsa eirsma eirsam eisarm eisamr eisram eisrma
eismra eismar ermias ermisa ermais ermasi ermsai ermsia erimas erimsa eriams
eriasm erisam erisma eraims eraism eramis eramsi erasmi erasim ersiam ersima
ersaim ersami ersmai ersmia esmira esmiar esmria esmrai esmari esmair esimra
esimar esirma esiram esiarm esiamr esrima esriam esrmia esrmai esrami esraim
esairm esaimr esarim esarmi esamri esamir samier samire sameir sameri samrei
samrie saimer saimre saiemr saierm sairem sairme saeimr saeirm saemir saemri
saermi saerim sariem sarime sareim saremi sarmei sarmie smaier smaire smaeir
smaeri smarei smarie smiaer smiare smiear smiera smirea smirae smeiar smeira
smeair smeari smerai smeria smriea smriae smreia smreai smraei smraie simaer
simare simear simera simrea simrae siamer siamre siaemr siaerm siarem siarme
sieamr siearm siemar siemra sierma sieram siraem sirame siream sirema sirmea
sirmae semiar semira semair semari semrai semria seimar seimra seiamr seiarm
seiram seirma seaimr seairm seamir seamri searmi searim seriam serima seraim
serami sermai sermia srmiea srmiae srmeia srmeai srmaei srmaie srimea srimae
sriema srieam sriaem sriame sreima sreiam sremia sremai sreami sreaim sraiem
sraime sraeim sraemi sramei sramie

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

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