Felo

Alphabet Reversal Substitution Translator Online

Convert text with the reversed-alphabet cipher: A becomes Z, B becomes Y, and so on through M and N. Unlike a bare two-box tool, it states its case policy, preserves spaces, digits and punctuation exactly, and works in both directions. Try it online.

What is Alphabet Reversal Substitution Translator Online?

Alphabet Reversal Substitution Translator Online is a conversational cipher tool for the reversed-alphabet substitution, often called the ABC-to-ZYX or upside-down alphabet cipher. Each Latin letter is swapped with its mirror partner: A with Z, B with Y, C with X, and so on until M and N trade places. The result looks like scrambled text but is fully reversible, because the same mapping undoes itself.

The agent does more than swap letters silently. It tells you which direction it applied, keeps your spaces, punctuation, digits and line breaks untouched, and explains how lowercase letters were handled so you are never guessing.

Key Features

Exact 26-letter mapping. Every conversion uses the complete fixed table from A↔Z through M↔N, applied by a deterministic script rather than by guesswork.
Both directions in one place. Paste plain text to encode it, or paste reversed text to decode it. The agent detects the likely direction and states its choice.
Faithful preservation. Spaces, tabs, line breaks, digits, emoji and punctuation pass through unchanged, so formatting survives the round trip.
Stated case policy. Lowercase letters are handled by an explicit rule you can see, instead of an all-caps workaround.
Verifiable output. The agent can show the mapping table and a short worked example so you can check the result yourself.

How to Use

Type or paste the text you want to convert, for example HELLO WORLD. If the direction is not obvious, say "encode" or "decode".
Read the converted text in the copyable block. The agent names the direction it used and notes anything it preserved or left alone.
Ask for a refinement if needed, such as "show the mapping table", "keep my lowercase letters lowercase", or "decode this back".

Example Use Cases

Playful messages to friends. Encode a short note like MEET ME AT NOON into its mirrored form so it reads as gibberish at a glance, then share the key so they can decode it.
Puzzle and escape-room design. Build a reversed-alphabet clue for a treasure hunt or classroom activity, and decode candidate answers to check they read correctly.
Checking a decoded string. Paste an unfamiliar reversed string such as SVOOL DLIOW and confirm it decodes to HELLO WORLD, with punctuation and spacing intact.

Tips for Best Results

Say the direction explicitly when your text is ambiguous, for example when it contains only letters like M and N that map to each other.
Remember the cipher is self-inverse: encoding twice returns the original, so you can always verify a result by running it again.
Keep the original text if you plan to compare; the agent does not store anything between sessions.

FAQ

What input format does it accept?
Any plain text: single words, sentences, multiple lines, digits, punctuation and emoji. Very long passages are handled, but extremely large inputs may be summarised with a note if a limit is reached.

How accurate is the result?
The mapping is a fixed 26-letter table applied by a deterministic script, so letter substitution is exact. The only judgement call is direction detection, which the agent states openly so you can correct it.

How is this different from some free text tools?
Some free text tools require all-caps input because of an unfixed bug and leave lowercase or punctuation behaviour undocumented. This agent states its case policy, preserves non-letter characters, and explains the mapping, while still performing the same core reversal cipher.

Does it produce images, fonts or audio?
No. The output is plain text only.