JavaScrypt: Browser-Based Cryptography

JavaScrypt: Browser-Based Cryptography is a  high-security data encryption solution which runs entirely in your Web browser. JavaScrypt's encryption facilities use the Advanced Encryption Standard (AES) adopted by the United States as Federal Information Processing Standard 197. AES supports key lengths of 128, 192, and 256 bits; JavaScrypt uses 256 bit keys exclusively.

I have long been a fan of John Walker's "JavaScrypt: Browser-Based Cryptography".

In March 2018, he made some updates to the program, making this a good time to again recommend that you download a copy of this excellent encryption program.

You can run JavaScrypt: Browser-Based Cryptography while on-line, but I recommend downloading  a copy and running it as a file within your browser. The downloaded and extracted (un-zipped) files are only 844 KB. Once you have all of the files saved to a folder on your computer, just click the "index.html" file and the program will run just like the web-page on-line, but you don't have to be connected to the Internet. JavaScrypt: Browser-Based Cryptography works precisely the same whether installed on your local computer or accessed over the Web. The only difference is that you use a "file:" URL to direct your browser to the local directory containing JavaScrypt rather than an "http:" URL pointing to a Web site.

Below is a message encrypted using JavaScrypt: Browser-Based Cryptography.

The password to decrypt this message is: H4M07TOV

#####  Encrypted: decrypt with http://www.fourmilab.ch/javascrypt/
ZZZZZ GNJPF IRXFA WFCRI IOXIQ OGREC GIHGG VFEWP WMSQF EDXQU BXUAE
UGUTB ARPKC ASEBB EGKWV SEXQT KIPXW QUBWT GBCEG TXKCK BCRVW XXTGS
IMVDA XWHBO QNTGD XGRNH DIOSU NDRLN IJDAV OITTW BCERE NTVMW DUVGL
XEBXG MNERJ WLPGE QXQBC ONWIP QHEAL FMQLB MUOJO PBGUG DTPKA XPHAO
DSDJV DAAHC AKRKJ AGUNR NTMXT XBNXC SQQKM SHMVU PLXGE JPQDQ PXVMK
XBSGO JECRE OUOJA IBOSC LDBNC OSMTV IOEFK VXVFG NXOJA INBPU PMAFI
IHGSK EXBGW AALLB PLSWD RXELS ABDLD VOSHG XLGQH KWIRU CKHNI GUTIF
AAJTQ OVOKT MTBHH VOQXG EAHVC QXSQT JVJGV JDBWB NAENQ OSPWW TUSVT
IAJXM IBQCW LDVTP GTMDA NSTFR RILCM BUUHV FMGRG IFPUV YYYYY
#####  End encrypted message