Caesar Cipher & ROT13
Encrypt and decrypt text with Caesar shift cipher (1-25) and ROT13 with brute-force table.
- 100% free
- Private in browser
- No signup
- No watermarks
Decrypted Text (Shift 13)
Hello World! The secret code is GurGbbyff 2026.
Brute-Force Decoder (All 25 Alphabet Shifts)
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About Caesar Cipher & ROT13
Caesar Cipher & ROT13 tool on TheToolss provides an interactive encryption and decryption workspace for classic shift ciphers. Choose any shift key between 1 and 25, activate ROT13 with one click, or view the complete 25-shift brute-force decoding table to quickly crack intercepted messages without knowing the key. 100% private in your browser.
How to use Caesar Cipher & ROT13
- Paste or type the text you want to encrypt or decrypt.
- Select your shift key value (1–25) or click ROT13 (Shift 13).
- View the converted text instantly, or inspect the brute-force table to identify the decoded message.
Key features
- Customizable Caesar shift offset from 1 to 25 positions
- One-click ROT13 (Rotate by 13 places) encode/decode toggle
- Automatic brute-force table displaying all 25 shift variations simultaneously
- Preserves casing, whitespace, and special punctuation characters
- 100% private client-side cryptography without remote logging
Frequently asked questions
- What is a Caesar cipher?
- A Caesar cipher is one of the oldest known substitution ciphers where each letter in the plaintext is shifted down the alphabet by a fixed number of positions (the shift key).
- What is ROT13?
- ROT13 is a special Caesar cipher with a shift key of 13. Because the English alphabet has 26 letters, applying ROT13 twice restores the original text.
- How do I crack a Caesar cipher if I do not know the key?
- Use the built-in "All 25 Shifts" brute-force table below. Simply scan the list to spot the row containing readable English text.
- Are numbers and punctuation shifted?
- Standard Caesar ciphers only shift alphabetical letters (A-Z, a-z). Numbers, spaces, and punctuation symbols remain unchanged.
- Is my secret text safe and private?
- Yes. All shifting and brute-force calculations happen directly in your browser. No text is ever uploaded or recorded.
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