Caesar cipher

Shift letters and reverse the result.

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Caesar cipher processes your input in this browser. Inputs and results are excluded from analytics. Recent tools save tool names, visit counts and last-visit times. Saved tools store only their names. Draft saving is optional and stays on this device; delete saved text with the draft controls. Loading text from a URL is optional and contacts that server; its URL and your IP address are visible to the server. An optional “Use in” action keeps a handoff in this tab. The next tool removes it on arrival and ignores it if more than a minute has passed.

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Letter shift

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Your result

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Updated 2026-09-26

Caesar cipher explained

Choose a whole-number shift for A–Z. Encoding moves letters forward; decoding moves them back. Punctuation, digits and non-Latin characters stay in place.

Next: ROT13 encoder decoder

Next: Vigenere cipher

A worked example

With a shift of 3, Zebra becomes Cheud. Decoding Cheud with the same shift returns Zebra.

Before you use the result

A historical letter puzzle, not secure encryption. Only the unaccented Latin alphabet changes; accents and other scripts remain unchanged.

Next: Base64 encoder and decoder

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ToolOctopus. “Caesar cipher.” Updated 2026-09-26. https://tooloctopus.com/caesar-cipher-tool.

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