Caesar Cipher
Encrypt and decrypt text using the Caesar cipher with a customizable shift value.
The Caesar Cipher is a fast, accurate Security utility designed to encrypt and decrypt text using the caesar cipher with a customizable shift value. entirely in your browser with zero server data storage.
The Caesar cipher shifts each letter by a fixed number of positions in the alphabet.
With shift 3: A → D, B → E
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Systems & Security Engineers • Applied Cryptography & High-Performance Web Tools
How to Use Caesar Cipher
Enter Text
Type or paste the message you want to encrypt or decrypt.
Set Shift Value
Use the slider to choose how many positions to shift letters (1-25).
Choose Case
Toggle to preserve or convert uppercase/lowercase.
Encrypt/Decrypt
Click to process your text.
Brute Force
Click to see all 25 possible decodings.
Practical Examples & Conversions
ABC
DEF
Related Tools & Converters
Authoritative Standards & Citations
Calculations and algorithms on this page are implemented and verified in strict accordance with the following official technical specifications:
RFC 6238: TOTP: Time-Based One-Time Password Algorithm
Extension of the HMAC-based One-Time Password algorithm HOTP to support time-based moving factors.
NIST Special Publication 800-38D: Galois/Counter Mode (GCM)
Recommendation for block cipher modes of operation: Galois/Counter Mode (GCM) and GMAC.