FileConverterPro

ROT13 / Caesar Cipher

Encode and decode text with ROT13 or any Caesar cipher shift online for free. Adjustable shift value from 1 to 25. Instant encryption and decryption.

Runs entirely in your browser — files never uploaded

13
125

Shifted alphabet (shift 13)

A→NB→OC→PD→QE→RF→SG→TH→UI→VJ→WK→XL→YM→ZN→AO→BP→CQ→DR→ES→FT→GU→HV→IW→JX→KY→LZ→M

Only letters (A-Z, a-z) are shifted. Numbers, punctuation, and spaces are preserved.

How to use ROT13 / Caesar Cipher

  1. 1. Enter your text. Type or paste the text you want to encode or decode into the input area.
  2. 2. Choose a shift value. Use the slider to pick a shift (1-25), or click a preset like ROT13 or ROT47.
  3. 3. Copy the result. The output updates in real time. Click Copy to grab the encoded or decoded text.

FAQ

What is ROT13?

ROT13 is a Caesar cipher that shifts each letter 13 positions in the alphabet. Since the Latin alphabet has 26 letters, applying ROT13 twice returns the original text.

What is the difference between encoding and decoding?

Encoding shifts letters forward by the chosen amount. Decoding shifts them backward by the same amount. With ROT13 (shift 13), encoding and decoding are the same operation.

Does it change numbers and punctuation?

Standard Caesar cipher only shifts letters. Numbers, punctuation, and spaces are preserved. ROT5 shifts digits only, and ROT47 shifts all printable ASCII characters.

Is my data uploaded anywhere?

No. Everything runs entirely in your browser.

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