NATO Phonetic Alphabet Converter

Reading a booking reference down a bad phone line is where this alphabet earns its keep, because M and N sound alike and Mike and November do not. The NATO Phonetic Alphabet Converter turns a string into code words and reads them back the other way, with a breakdown grid showing which characters it recognised and which it could not.

Encoding uppercases your input, maps each character through a table of 36 entries covering A to Z and 0 to 9, and joins the results with a spaced em dash. SOS comes back as Sierra — Oscar — Sierra. A space in your text becomes the marker [SPACE] instead of disappearing, which is what lets a multi-word string survive a round trip.

Decoding lowercases everything, treats the em dash as whitespace, and looks each word up in the reversed table. Words it cannot place pass through unchanged rather than being dropped, so a decoded line shows you exactly where a sequence went wrong. The tables live in the page and no request is made.

The Controls and the Breakdown Grid

• Text → NATO and NATO → Text set the direction, and switching clears the input, because code words left sitting in text mode would be spelled out letter by letter.
• Character Breakdown appears in encode mode and gives each character its own card, the character above its code word. Anything unmapped gets a red-tinted card reading ?, which is far easier to scan than hunting through the joined output.
• The NATO Reference Chart at the foot is interactive. Clicking a row appends that letter to your input rather than copying it, turning the chart into a keypad for assembling a reference by hand.
• Five sample chips sit under Try: in encode mode, among them SOS and Password123, the second of which is there to demonstrate digit handling.
• Copy lifts the joined output and flashes a Copied! 🚀 badge above the button for 1.5 seconds.

Tricky Inputs: Digits, Spaces and Round-Trips

• Digits carry code words, so 7 becomes Seven and 0 becomes Zero. The reference chart lists letters only, so those 10 rows work without being displayed.
• Punctuation has no mapping and passes through as itself. The hyphen in ACME-1 shows up in the output as a bare -, and its breakdown card turns red.
• Decoding accepts space as readily as [SPACE], because people say the word rather than the bracketed marker when reading a sequence aloud.
• Unrecognised words survive decoding intact. Misspell one code word in a pasted sequence and it appears in the result verbatim, pointing straight at the fault.
• Both directions are case-blind, so decoded text always returns uppercase. Round-tripping Hello hands back HELLO.

The ICAO Spellings and Their Limits

• This table writes Alpha and Juliet. ICAO documents spell them Alfa and Juliett on purpose, so that speakers of languages where ph is not an F sound, or a lone final t falls silent, still say them correctly.
• Decoding is strict about the spelling it stores. Type Alfa and you get back the literal word alfa, not the letter A.
• X-ray holds a hyphen and stays one token, so it survives the whitespace split. Written Xray it will not decode.
• Digit words use plain English forms. Aviation radio says Niner for 9 and Tree for 3 to survive a noisy channel; this chart says Nine and Three.
• There is no pronunciation guide and no audio here. The tool converts spellings, and the stress patterns that go with them are not something the table holds.