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: bruhns
cipher variations:
csviot dtwjpu euxkqv fvylrw gwzmsx
hxanty iybouz jzcpva kadqwb lberxc
mcfsyd ndgtze oehuaf pfivbg qgjwch
rhkxdi silyej tjmzfk uknagl vlobhm
wmpcin xnqdjo yorekp zpsflq aqtgmr

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: bruhns
Cipher: yifsmh

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: bruhns

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: bruhns
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: bruhns
Cipher: oehuaf

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: bruhns
Cipher: 212454323334

Extended Methods:
Method #1

Plaintext: bruhns
method variations:

Method #2
Bifid cipher
The message is converted to its coordinates in the usual manner, but they are written vertically beneath:
b r u h n s 
2 2 5 3 3 3 
1 4 4 2 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: bruhns
Cipher: gpnqis

Read more ...
Method #3

Plaintext: bruhns
method variations:
fyomni yomnif omnify
mnifyo nifyom ifyomn

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: bruhns

all 720 cipher variations:
bruhns bruhsn brunhs brunsh brusnh brushn brhuns brhusn brhnus brhnsu brhsnu
brhsun brnhus brnhsu brnuhs brnush brnsuh brnshu brshnu brshun brsnhu brsnuh
brsunh brsuhn burhns burhsn burnhs burnsh bursnh burshn buhrns buhrsn buhnrs
buhnsr buhsnr buhsrn bunhrs bunhsr bunrhs bunrsh bunsrh bunshr bushnr bushrn
busnhr busnrh busrnh busrhn bhurns bhursn bhunrs bhunsr bhusnr bhusrn bhruns
bhrusn bhrnus bhrnsu bhrsnu bhrsun bhnrus bhnrsu bhnurs bhnusr bhnsur bhnsru
bhsrnu bhsrun bhsnru bhsnur bhsunr bhsurn bnuhrs bnuhsr bnurhs bnursh bnusrh
bnushr bnhurs bnhusr bnhrus bnhrsu bnhsru bnhsur bnrhus bnrhsu bnruhs bnrush
bnrsuh bnrshu bnshru bnshur bnsrhu bnsruh bnsurh bnsuhr bsuhnr bsuhrn bsunhr
bsunrh bsurnh bsurhn bshunr bshurn bshnur bshnru bshrnu bshrun bsnhur bsnhru
bsnuhr bsnurh bsnruh bsnrhu bsrhnu bsrhun bsrnhu bsrnuh bsrunh bsruhn rbuhns
rbuhsn rbunhs rbunsh rbusnh rbushn rbhuns rbhusn rbhnus rbhnsu rbhsnu rbhsun
rbnhus rbnhsu rbnuhs rbnush rbnsuh rbnshu rbshnu rbshun rbsnhu rbsnuh rbsunh
rbsuhn rubhns rubhsn rubnhs rubnsh rubsnh rubshn ruhbns ruhbsn ruhnbs ruhnsb
ruhsnb ruhsbn runhbs runhsb runbhs runbsh runsbh runshb rushnb rushbn rusnhb
rusnbh rusbnh rusbhn rhubns rhubsn rhunbs rhunsb rhusnb rhusbn rhbuns rhbusn
rhbnus rhbnsu rhbsnu rhbsun rhnbus rhnbsu rhnubs rhnusb rhnsub rhnsbu rhsbnu
rhsbun rhsnbu rhsnub rhsunb rhsubn rnuhbs rnuhsb rnubhs rnubsh rnusbh rnushb
rnhubs rnhusb rnhbus rnhbsu rnhsbu rnhsub rnbhus rnbhsu rnbuhs rnbush rnbsuh
rnbshu rnshbu rnshub rnsbhu rnsbuh rnsubh rnsuhb rsuhnb rsuhbn rsunhb rsunbh
rsubnh rsubhn rshunb rshubn rshnub rshnbu rshbnu rshbun rsnhub rsnhbu rsnuhb
rsnubh rsnbuh rsnbhu rsbhnu rsbhun rsbnhu rsbnuh rsbunh rsbuhn urbhns urbhsn
urbnhs urbnsh urbsnh urbshn urhbns urhbsn urhnbs urhnsb urhsnb urhsbn urnhbs
urnhsb urnbhs urnbsh urnsbh urnshb urshnb urshbn ursnhb ursnbh ursbnh ursbhn
ubrhns ubrhsn ubrnhs ubrnsh ubrsnh ubrshn ubhrns ubhrsn ubhnrs ubhnsr ubhsnr
ubhsrn ubnhrs ubnhsr ubnrhs ubnrsh ubnsrh ubnshr ubshnr ubshrn ubsnhr ubsnrh
ubsrnh ubsrhn uhbrns uhbrsn uhbnrs uhbnsr uhbsnr uhbsrn uhrbns uhrbsn uhrnbs
uhrnsb uhrsnb uhrsbn uhnrbs uhnrsb uhnbrs uhnbsr uhnsbr uhnsrb uhsrnb uhsrbn
uhsnrb uhsnbr uhsbnr uhsbrn unbhrs unbhsr unbrhs unbrsh unbsrh unbshr unhbrs
unhbsr unhrbs unhrsb unhsrb unhsbr unrhbs unrhsb unrbhs unrbsh unrsbh unrshb
unshrb unshbr unsrhb unsrbh unsbrh unsbhr usbhnr usbhrn usbnhr usbnrh usbrnh
usbrhn ushbnr ushbrn ushnbr ushnrb ushrnb ushrbn usnhbr usnhrb usnbhr usnbrh
usnrbh usnrhb usrhnb usrhbn usrnhb usrnbh usrbnh usrbhn hrubns hrubsn hrunbs
hrunsb hrusnb hrusbn hrbuns hrbusn hrbnus hrbnsu hrbsnu hrbsun hrnbus hrnbsu
hrnubs hrnusb hrnsub hrnsbu hrsbnu hrsbun hrsnbu hrsnub hrsunb hrsubn hurbns
hurbsn hurnbs hurnsb hursnb hursbn hubrns hubrsn hubnrs hubnsr hubsnr hubsrn
hunbrs hunbsr hunrbs hunrsb hunsrb hunsbr husbnr husbrn husnbr husnrb husrnb
husrbn hburns hbursn hbunrs hbunsr hbusnr hbusrn hbruns hbrusn hbrnus hbrnsu
hbrsnu hbrsun hbnrus hbnrsu hbnurs hbnusr hbnsur hbnsru hbsrnu hbsrun hbsnru
hbsnur hbsunr hbsurn hnubrs hnubsr hnurbs hnursb hnusrb hnusbr hnburs hnbusr
hnbrus hnbrsu hnbsru hnbsur hnrbus hnrbsu hnrubs hnrusb hnrsub hnrsbu hnsbru
hnsbur hnsrbu hnsrub hnsurb hnsubr hsubnr hsubrn hsunbr hsunrb hsurnb hsurbn
hsbunr hsburn hsbnur hsbnru hsbrnu hsbrun hsnbur hsnbru hsnubr hsnurb hsnrub
hsnrbu hsrbnu hsrbun hsrnbu hsrnub hsrunb hsrubn nruhbs nruhsb nrubhs nrubsh
nrusbh nrushb nrhubs nrhusb nrhbus nrhbsu nrhsbu nrhsub nrbhus nrbhsu nrbuhs
nrbush nrbsuh nrbshu nrshbu nrshub nrsbhu nrsbuh nrsubh nrsuhb nurhbs nurhsb
nurbhs nurbsh nursbh nurshb nuhrbs nuhrsb nuhbrs nuhbsr nuhsbr nuhsrb nubhrs
nubhsr nubrhs nubrsh nubsrh nubshr nushbr nushrb nusbhr nusbrh nusrbh nusrhb
nhurbs nhursb nhubrs nhubsr nhusbr nhusrb nhrubs nhrusb nhrbus nhrbsu nhrsbu
nhrsub nhbrus nhbrsu nhburs nhbusr nhbsur nhbsru nhsrbu nhsrub nhsbru nhsbur
nhsubr nhsurb nbuhrs nbuhsr nburhs nbursh nbusrh nbushr nbhurs nbhusr nbhrus
nbhrsu nbhsru nbhsur nbrhus nbrhsu nbruhs nbrush nbrsuh nbrshu nbshru nbshur
nbsrhu nbsruh nbsurh nbsuhr nsuhbr nsuhrb nsubhr nsubrh nsurbh nsurhb nshubr
nshurb nshbur nshbru nshrbu nshrub nsbhur nsbhru nsbuhr nsburh nsbruh nsbrhu
nsrhbu nsrhub nsrbhu nsrbuh nsrubh nsruhb sruhnb sruhbn srunhb srunbh srubnh
srubhn srhunb srhubn srhnub srhnbu srhbnu srhbun srnhub srnhbu srnuhb srnubh
srnbuh srnbhu srbhnu srbhun srbnhu srbnuh srbunh srbuhn surhnb surhbn surnhb
surnbh surbnh surbhn suhrnb suhrbn suhnrb suhnbr suhbnr suhbrn sunhrb sunhbr
sunrhb sunrbh sunbrh sunbhr subhnr subhrn subnhr subnrh subrnh subrhn shurnb
shurbn shunrb shunbr shubnr shubrn shrunb shrubn shrnub shrnbu shrbnu shrbun
shnrub shnrbu shnurb shnubr shnbur shnbru shbrnu shbrun shbnru shbnur shbunr
shburn snuhrb snuhbr snurhb snurbh snubrh snubhr snhurb snhubr snhrub snhrbu
snhbru snhbur snrhub snrhbu snruhb snrubh snrbuh snrbhu snbhru snbhur snbrhu
snbruh snburh snbuhr sbuhnr sbuhrn sbunhr sbunrh sburnh sburhn sbhunr sbhurn
sbhnur sbhnru sbhrnu sbhrun sbnhur sbnhru sbnuhr sbnurh sbnruh sbnrhu sbrhnu
sbrhun sbrnhu sbrnuh sbrunh sbruhn

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

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