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: darvon
cipher variations:
ebswpo fctxqp gduyrq hevzsr ifwats
jgxbut khycvu lizdwv mjaexw nkbfyx
olcgzy pmdhaz qneiba rofjcb spgkdc
tqhled urimfe vsjngf wtkohg xulpih
yvmqji zwnrkj axoslk byptml czqunm

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: darvon
Cipher: wzielm

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: darvon

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: darvon
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: darvon
Cipher: qneiba

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: darvon
Cipher: 411124154333

Extended Methods:
Method #1

Plaintext: darvon
method variations:

Method #2
Bifid cipher
The message is converted to its coordinates in the usual manner, but they are written vertically beneath:
d a r v o n 
4 1 2 1 4 3 
1 1 4 5 3 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: darvon
Cipher: dboayn

Read more ...
Method #3

Plaintext: darvon
method variations:
afduns fdunsa dunsaf
unsafd nsafdu safdun

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: darvon

all 720 cipher variations:
darvon darvno darovn daronv darnov darnvo davron davrno davorn davonr davnor
davnro daovrn daovnr daorvn daornv daonrv daonvr danvor danvro danovr danorv
danrov danrvo dravon dravno draovn draonv dranov dranvo drvaon drvano drvoan
drvona drvnoa drvnao drovan drovna droavn droanv dronav dronva drnvoa drnvao
drnova drnoav drnaov drnavo dvraon dvrano dvroan dvrona dvrnoa dvrnao dvaron
dvarno dvaorn dvaonr dvanor dvanro dvoarn dvoanr dvoran dvorna dvonra dvonar
dvnaor dvnaro dvnoar dvnora dvnroa dvnrao dorvan dorvna doravn doranv dornav
dornva dovran dovrna dovarn dovanr dovnar dovnra doavrn doavnr doarvn doarnv
doanrv doanvr donvar donvra donavr donarv donrav donrva dnrvoa dnrvao dnrova
dnroav dnraov dnravo dnvroa dnvrao dnvora dnvoar dnvaor dnvaro dnovra dnovar
dnorva dnorav dnoarv dnoavr dnavor dnavro dnaovr dnaorv dnarov dnarvo adrvon
adrvno adrovn adronv adrnov adrnvo advron advrno advorn advonr advnor advnro
adovrn adovnr adorvn adornv adonrv adonvr adnvor adnvro adnovr adnorv adnrov
adnrvo ardvon ardvno ardovn ardonv ardnov ardnvo arvdon arvdno arvodn arvond
arvnod arvndo arovdn arovnd arodvn arodnv arondv aronvd arnvod arnvdo arnovd
arnodv arndov arndvo avrdon avrdno avrodn avrond avrnod avrndo avdron avdrno
avdorn avdonr avdnor avdnro avodrn avodnr avordn avornd avonrd avondr avndor
avndro avnodr avnord avnrod avnrdo aorvdn aorvnd aordvn aordnv aorndv aornvd
aovrdn aovrnd aovdrn aovdnr aovndr aovnrd aodvrn aodvnr aodrvn aodrnv aodnrv
aodnvr aonvdr aonvrd aondvr aondrv aonrdv aonrvd anrvod anrvdo anrovd anrodv
anrdov anrdvo anvrod anvrdo anvord anvodr anvdor anvdro anovrd anovdr anorvd
anordv anodrv anodvr andvor andvro andovr andorv androv andrvo radvon radvno
radovn radonv radnov radnvo ravdon ravdno ravodn ravond ravnod ravndo raovdn
raovnd raodvn raodnv raondv raonvd ranvod ranvdo ranovd ranodv randov randvo
rdavon rdavno rdaovn rdaonv rdanov rdanvo rdvaon rdvano rdvoan rdvona rdvnoa
rdvnao rdovan rdovna rdoavn rdoanv rdonav rdonva rdnvoa rdnvao rdnova rdnoav
rdnaov rdnavo rvdaon rvdano rvdoan rvdona rvdnoa rvdnao rvadon rvadno rvaodn
rvaond rvanod rvando rvoadn rvoand rvodan rvodna rvonda rvonad rvnaod rvnado
rvnoad rvnoda rvndoa rvndao rodvan rodvna rodavn rodanv rodnav rodnva rovdan
rovdna rovadn rovand rovnad rovnda roavdn roavnd roadvn roadnv roandv roanvd
ronvad ronvda ronavd ronadv rondav rondva rndvoa rndvao rndova rndoav rndaov
rndavo rnvdoa rnvdao rnvoda rnvoad rnvaod rnvado rnovda rnovad rnodva rnodav
rnoadv rnoavd rnavod rnavdo rnaovd rnaodv rnadov rnadvo vardon vardno varodn
varond varnod varndo vadron vadrno vadorn vadonr vadnor vadnro vaodrn vaodnr
vaordn vaornd vaonrd vaondr vandor vandro vanodr vanord vanrod vanrdo vradon
vradno vraodn vraond vranod vrando vrdaon vrdano vrdoan vrdona vrdnoa vrdnao
vrodan vrodna vroadn vroand vronad vronda vrndoa vrndao vrnoda vrnoad vrnaod
vrnado vdraon vdrano vdroan vdrona vdrnoa vdrnao vdaron vdarno vdaorn vdaonr
vdanor vdanro vdoarn vdoanr vdoran vdorna vdonra vdonar vdnaor vdnaro vdnoar
vdnora vdnroa vdnrao vordan vordna voradn vorand vornad vornda vodran vodrna
vodarn vodanr vodnar vodnra voadrn voadnr voardn voarnd voanrd voandr vondar
vondra vonadr vonard vonrad vonrda vnrdoa vnrdao vnroda vnroad vnraod vnrado
vndroa vndrao vndora vndoar vndaor vndaro vnodra vnodar vnorda vnorad vnoard
vnoadr vnador vnadro vnaodr vnaord vnarod vnardo oarvdn oarvnd oardvn oardnv
oarndv oarnvd oavrdn oavrnd oavdrn oavdnr oavndr oavnrd oadvrn oadvnr oadrvn
oadrnv oadnrv oadnvr oanvdr oanvrd oandvr oandrv oanrdv oanrvd oravdn oravnd
oradvn oradnv orandv oranvd orvadn orvand orvdan orvdna orvnda orvnad ordvan
ordvna ordavn ordanv ordnav ordnva ornvda ornvad orndva orndav ornadv ornavd
ovradn ovrand ovrdan ovrdna ovrnda ovrnad ovardn ovarnd ovadrn ovadnr ovandr
ovanrd ovdarn ovdanr ovdran ovdrna ovdnra ovdnar ovnadr ovnard ovndar ovndra
ovnrda ovnrad odrvan odrvna odravn odranv odrnav odrnva odvran odvrna odvarn
odvanr odvnar odvnra odavrn odavnr odarvn odarnv odanrv odanvr odnvar odnvra
odnavr odnarv odnrav odnrva onrvda onrvad onrdva onrdav onradv onravd onvrda
onvrad onvdra onvdar onvadr onvard ondvra ondvar ondrva ondrav ondarv ondavr
onavdr onavrd onadvr onadrv onardv onarvd narvod narvdo narovd narodv nardov
nardvo navrod navrdo navord navodr navdor navdro naovrd naovdr naorvd naordv
naodrv naodvr nadvor nadvro nadovr nadorv nadrov nadrvo nravod nravdo nraovd
nraodv nradov nradvo nrvaod nrvado nrvoad nrvoda nrvdoa nrvdao nrovad nrovda
nroavd nroadv nrodav nrodva nrdvoa nrdvao nrdova nrdoav nrdaov nrdavo nvraod
nvrado nvroad nvroda nvrdoa nvrdao nvarod nvardo nvaord nvaodr nvador nvadro
nvoard nvoadr nvorad nvorda nvodra nvodar nvdaor nvdaro nvdoar nvdora nvdroa
nvdrao norvad norvda noravd noradv nordav nordva novrad novrda novard novadr
novdar novdra noavrd noavdr noarvd noardv noadrv noadvr nodvar nodvra nodavr
nodarv nodrav nodrva ndrvoa ndrvao ndrova ndroav ndraov ndravo ndvroa ndvrao
ndvora ndvoar ndvaor ndvaro ndovra ndovar ndorva ndorav ndoarv ndoavr ndavor
ndavro ndaovr ndaorv ndarov ndarvo

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

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