Katakana: The Second Syllabary

Japanese has two kana syllabaries, and they are phonetic twins. Katakana (カタカナ) covers exactly the same 46 basic sounds as hiragana — the same gojūon grid, the same readings — but in a sharper, more angular form. カ and か both say ka; ミ and み both say mi. If you know the hiragana grid, you already know how katakana sounds; you only need to learn how it looks.

The temptation is to treat katakana as an advanced topic and put it off. That is a mistake. Katakana is where most modern vocabulary enters Japanese, so you meet it immediately — on menus, station signs, product labels, and in the first coffee you order. Neglect it and you will be functionally illiterate in exactly the places tourists and beginners spend their time.

Same sounds, different clothes

Every katakana character corresponds one-to-one to a hiragana character in sound. Here are a few pairs so the parallel is concrete:

The voicing marks work identically too: just as か → が with dakuten, カ → ガ. The small っ, the small ゃゅょ of combined kana — all of it carries straight over. The full katakana grid, character by character, is on the reading the katakana grid page.

What katakana is for

Katakana is not a random alternative to hiragana; it marks a word as belonging to a particular category. In broad strokes, katakana is used for:

• Loanwords (外来語, gairaigo) — words borrowed from other languages: コーヒー (coffee), テレビ (television), パン (bread, from Portuguese pão).
• Foreign names and places — personal names, countries, cities: アメリカ (America), マリア (Maria).
• Onomatopoeia, especially sharp or mechanical sounds: ワンワン (a dog's "woof"), ガチャ (a click/clunk).
• Scientific and technical terms — species names, chemical names, and much technical jargon.
• Emphasis — a native word written in katakana instead of its usual hiragana or kanji, to stand out, the way English uses italics or ALL CAPS.

For the full breakdown of each category, see When Katakana Is Used; for the choice between scripts, see Hiragana vs Katakana.

Katakana loanwords are Japanese words, not English

This is the single most important insight on the page, and the one that saves the most embarrassment. A katakana loanword has been fully absorbed into Japanese. It is reshaped to fit Japanese sounds and given Japanese timing, and from that point on it is a Japanese word — not the English word it came from.

So コーヒー is not "coffee." It is kōhī: four moras, ko - o - hi - i, with a long o and a long i and no English vowels anywhere. Say "coffee" with an English accent and a Japanese listener may genuinely not understand you; say kōhī and you will be handed a cup.

Notice how thoroughly the sounds are rebuilt: "restaurant" becomes four clean moras plus a vowel Japanese adds to break up consonant clusters (re-su-to-ran), and "smartphone" is not just adapted but clipped to スマホ. Reading these back with English pronunciation is the classic beginner error.

The angular look — and the characters that trick you

Where hiragana is rounded and flowing (derived from cursive kanji), katakana is angular and clipped (derived from fragments of kanji). That sharpness makes katakana quick to write but also makes several characters look dangerously alike. Four in particular catch nearly every learner:

The reliable way to tell シ/ツ and ソ/ン apart is stroke direction, not overall shape — a technique worth its own treatment on the katakana grid page. For now, just know these confusables exist, and that misreading シ as ツ turns タクシー (takushī, "taxi") into gibberish.

Common mistakes

The pattern behind these errors is the same: treating katakana as either optional or as a code for English. It is neither. It is a full working script for a large slice of the modern vocabulary, and the words in it are pronounced by their kana like any other Japanese word.

Key takeaways

• Katakana is hiragana's phonetic twin — the same 46 sounds, the same grid — in an angular form.
• It marks loanwords, foreign names, onomatopoeia, technical terms, and emphasis.
• Katakana loanwords are Japanese words: コーヒー is kōhī, not "coffee." Read them mora by mora.
• It is not advanced — beginners meet it immediately on menus, signs, and packaging.
• Watch the confusable pairs シ/ツ and ソ/ン; the discriminator is stroke direction, covered next.

Continue to Reading the Katakana Grid to learn the characters row by row.