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Caesar Cipher

CryptographyDataDeveloper
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Shift 13 = ROT13
Encoding and decoding use the same algorithm with opposite directions
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Guide

What is Caesar Cipher?

The Caesar cipher is one of the oldest known encryption techniques, named after Julius Caesar who used it for military communications. It works by shifting each letter in the text by a fixed number of positions in the alphabet.

Shift Example (HELLO)
1 IFMMP
3 KHOOR
13 (ROT13) URYYB

How It Works

  • Each letter shifts forward by the chosen amount
  • Letters wrap around: Z + 1 = A
  • Numbers and symbols stay unchanged
  • To decode, shift backwards by the same amount

Key Features

  • Adjustable shift (1-25)
  • Real-time encoding as you type
  • Preserves case and spacing
  • Copy result with one click

How to Use

  1. Enter your text
  2. Select the shift value (1-25)
  3. View the encoded result instantly
  4. To decode, use the reverse shift (26 minus original shift)

FAQs

  • Is Caesar cipher secure?
    No. With only 25 possible shifts, it can be broken in seconds. Use it for puzzles and learning, not security.
  • What is ROT13?
    ROT13 is Caesar cipher with shift 13. Since 13 is half of 26, the same operation encodes and decodes.

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