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: enlard
cipher variations:
fombse gpnctf hqodug irpevh jsqfwi
ktrgxj lushyk mvtizl nwujam oxvkbn
pywlco qzxmdp rayneq sbzofr tcapgs
udbqht vecriu wfdsjv xgetkw yhfulx
zigvmy ajhwnz bkixoa cljypb dmkzqc

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: enlard
Cipher: vmoziw

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: enlard

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: enlard
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: enlard
Cipher: rayneq

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: enlard
Cipher: 513313112441

Extended Methods:
Method #1

Plaintext: enlard
method variations:

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

Read more ...
Method #3

Plaintext: enlard
method variations:
lccftv ccftvl cftvlc
ftvlcc tvlccf vlccft

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: enlard

all 720 cipher variations:
enlard enladr enlrad enlrda enldra enldar enalrd enaldr enarld enardl enadrl
enadlr enrald enradl enrlad enrlda enrdla enrdal endarl endalr endral endrla
endlra endlar elnard elnadr elnrad elnrda elndra elndar elanrd elandr elarnd
elardn eladrn eladnr elrand elradn elrnad elrnda elrdna elrdan eldarn eldanr
eldran eldrna eldnra eldnar ealnrd ealndr ealrnd ealrdn ealdrn ealdnr eanlrd
eanldr eanrld eanrdl eandrl eandlr earnld earndl earlnd earldn eardln eardnl
eadnrl eadnlr eadrnl eadrln eadlrn eadlnr erland erladn erlnad erlnda erldna
erldan eralnd eraldn eranld erandl eradnl eradln ernald ernadl ernlad ernlda
erndla erndal erdanl erdaln erdnal erdnla erdlna erdlan edlarn edlanr edlran
edlrna edlnra edlnar edalrn edalnr edarln edarnl edanrl edanlr edraln edranl
edrlan edrlna edrnla edrnal ednarl ednalr ednral ednrla ednlra ednlar nelard
neladr nelrad nelrda neldra neldar nealrd nealdr nearld neardl neadrl neadlr
nerald neradl nerlad nerlda nerdla nerdal nedarl nedalr nedral nedrla nedlra
nedlar nleard nleadr nlerad nlerda nledra nledar nlaerd nlaedr nlared nlarde
nladre nlader nlraed nlrade nlread nlreda nlrdea nlrdae nldare nldaer nldrae
nldrea nldera nldear nalerd naledr nalred nalrde naldre nalder naelrd naeldr
naerld naerdl naedrl naedlr nareld naredl narled narlde nardle nardel naderl
nadelr nadrel nadrle nadlre nadler nrlaed nrlade nrlead nrleda nrldea nrldae
nraled nralde nraeld nraedl nradel nradle nreald nreadl nrelad nrelda nredla
nredal nrdael nrdale nrdeal nrdela nrdlea nrdlae ndlare ndlaer ndlrae ndlrea
ndlera ndlear ndalre ndaler ndarle ndarel ndaerl ndaelr ndrale ndrael ndrlae
ndrlea ndrela ndreal ndearl ndealr nderal nderla ndelra ndelar lneard lneadr
lnerad lnerda lnedra lnedar lnaerd lnaedr lnared lnarde lnadre lnader lnraed
lnrade lnread lnreda lnrdea lnrdae lndare lndaer lndrae lndrea lndera lndear
lenard lenadr lenrad lenrda lendra lendar leanrd leandr learnd leardn leadrn
leadnr lerand leradn lernad lernda lerdna lerdan ledarn ledanr ledran ledrna
lednra lednar laenrd laendr laernd laerdn laedrn laednr lanerd lanedr lanred
lanrde landre lander larned larnde larend laredn larden lardne ladnre ladner
ladrne ladren ladern ladenr lreand lreadn lrenad lrenda lredna lredan lraend
lraedn lraned lrande lradne lraden lrnaed lrnade lrnead lrneda lrndea lrndae
lrdane lrdaen lrdnae lrdnea lrdena lrdean ldearn ldeanr lderan lderna ldenra
ldenar ldaern ldaenr ldaren ldarne ldanre ldaner ldraen ldrane ldrean ldrena
ldrnea ldrnae ldnare ldnaer ldnrae ldnrea ldnera ldnear anlerd anledr anlred
anlrde anldre anlder anelrd aneldr anerld anerdl anedrl anedlr anreld anredl
anrled anrlde anrdle anrdel anderl andelr andrel andrle andlre andler alnerd
alnedr alnred alnrde alndre alnder alenrd alendr alernd alerdn aledrn alednr
alrend alredn alrned alrnde alrdne alrden aldern aldenr aldren aldrne aldnre
aldner aelnrd aelndr aelrnd aelrdn aeldrn aeldnr aenlrd aenldr aenrld aenrdl
aendrl aendlr aernld aerndl aerlnd aerldn aerdln aerdnl aednrl aednlr aedrnl
aedrln aedlrn aedlnr arlend arledn arlned arlnde arldne arlden arelnd areldn
arenld arendl arednl aredln arneld arnedl arnled arnlde arndle arndel ardenl
ardeln ardnel ardnle ardlne ardlen adlern adlenr adlren adlrne adlnre adlner
adelrn adelnr aderln adernl adenrl adenlr adreln adrenl adrlen adrlne adrnle
adrnel adnerl adnelr adnrel adnrle adnlre adnler rnlaed rnlade rnlead rnleda
rnldea rnldae rnaled rnalde rnaeld rnaedl rnadel rnadle rneald rneadl rnelad
rnelda rnedla rnedal rndael rndale rndeal rndela rndlea rndlae rlnaed rlnade
rlnead rlneda rlndea rlndae rlaned rlande rlaend rlaedn rladen rladne rleand
rleadn rlenad rlenda rledna rledan rldaen rldane rldean rldena rldnea rldnae
ralned ralnde ralend raledn ralden raldne ranled ranlde raneld ranedl randel
randle raenld raendl raelnd raeldn raedln raednl radnel radnle radenl radeln
radlen radlne reland reladn relnad relnda reldna reldan realnd realdn reanld
reandl readnl readln renald renadl renlad renlda rendla rendal redanl redaln
rednal rednla redlna redlan rdlaen rdlane rdlean rdlena rdlnea rdlnae rdalen
rdalne rdaeln rdaenl rdanel rdanle rdealn rdeanl rdelan rdelna rdenla rdenal
rdnael rdnale rdneal rdnela rdnlea rdnlae dnlare dnlaer dnlrae dnlrea dnlera
dnlear dnalre dnaler dnarle dnarel dnaerl dnaelr dnrale dnrael dnrlae dnrlea
dnrela dnreal dnearl dnealr dneral dnerla dnelra dnelar dlnare dlnaer dlnrae
dlnrea dlnera dlnear dlanre dlaner dlarne dlaren dlaern dlaenr dlrane dlraen
dlrnae dlrnea dlrena dlrean dlearn dleanr dleran dlerna dlenra dlenar dalnre
dalner dalrne dalren dalern dalenr danlre danler danrle danrel danerl danelr
darnle darnel darlne darlen dareln darenl daenrl daenlr daernl daerln daelrn
daelnr drlane drlaen drlnae drlnea drlena drlean dralne dralen dranle dranel
draenl draeln drnale drnael drnlae drnlea drnela drneal dreanl drealn drenal
drenla drelna drelan delarn delanr delran delrna delnra delnar dealrn dealnr
dearln dearnl deanrl deanlr deraln deranl derlan derlna dernla dernal denarl
denalr denral denrla denlra denlar

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

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