Caesar Cipher — Free Online Tool
Use Caesar Cipher free online — no sign-up required. Fast, secure, and works in all modern browsers.
Input Text
Encoded Output (shift 3)
Alphabet Mapping (shift 3)
A→DB→EC→FD→GE→HF→IG→JH→KI→LJ→MK→NL→OM→PN→QO→RP→SQ→TR→US→VT→WU→XV→YW→ZX→AY→BZ→C
Non-letter characters (spaces, numbers, punctuation) are left unchanged. Case is preserved.
Frequently Asked Questions about Caesar Cipher
- Is Caesar Cipher completely free?
- Yes, Caesar Cipher is 100% free with no registration, no usage limits, and no hidden costs. Use it as many times as you need.
- Is my data private?
- Caesar Cipher runs entirely in your browser — nothing is ever sent to our servers. Your data stays on your device at all times.
- Does it work offline?
- Once the page has loaded, Caesar Cipher works fully in your browser without an internet connection.
- Is the encoding/decoding reversible?
- Yes, all encoding operations are fully reversible. Use the same tool to encode and decode.
- Can I use it on my phone or tablet?
- Yes, Caesar Cipher is fully responsive and works on smartphones and tablets with any modern browser.
This tool runs entirely in your browser. No data is ever sent to our servers.