Translate a Flutter app into Italian: your .arb files, kept intact

What Italian changes in a Flutter UI

Italian runs noticeably longer than English. ‘Save’ becomes Salva, but ‘Settings’ becomes Impostazioni and ‘Sign out’ Esci dall'account or Disconnetti. In a fixed-width Row or a tab bar, that is where the yellow-and-black overflow stripes show up in debug mode.

• Register. The translation uses the formal register (Lei): Inserisca il codice. Many Italian consumer apps address users informally (Inserisci il codice) or use a neutral infinitive (Inserire il codice). Decide this before release, and review those strings if your brand uses the informal tu.
• Accents. è, più, perché, città. At the start of a sentence the correct capital is È, not E'. If you bundle a custom font subset to a limited character set, make sure the accented vowels are included.
• Gender and agreement. Participles agree with the noun: file eliminato, but foto eliminata and foto eliminate. A string that drops a variable noun into a fixed sentence can end up wrong depending on what is inserted.
• Apostrophes. Italian is full of them: l'utente, un'immagine, dell'app. They matter inside ICU messages, as explained below.

one, many, other: Italian plurals and ICU placeholders

The CLDR plural categories for Italian are one, many and other. An English template usually has only one and other; Manuce adds the missing category to the Italian value. For example:

{count, plural, =0{Nessun file} one{{count} file eliminato} many{{count} file eliminati} other{{count} file eliminati}}

The many branch only applies to very large round numbers (millions). With a count shown in digits it simply repeats the other text; it only differs for a spelt-out form such as un milione di file.

• Placeholders. {name}, {count} and {date} stay untouched, but they may move: {count} photos shared by {name} becomes {name} ha condiviso {count} foto. Every translated value is compared with the source; if a placeholder goes missing and the mismatch persists, the source value is kept and the report says so.
• Select. Existing select branches are translated, for instance {gender, select, female{Benvenuta} male{Benvenuto} other{Le diamo il benvenuto}}. If your source only says Welcome, {name}, the file has no gender branch: review that string, as a neutral phrasing like Le diamo il benvenuto, {name} avoids guessing the agreement.
• Apostrophes and escaping. If your generation settings enable single-quote escaping, the ' in l'utente may be read as the start of quoted text inside an ICU message. Check that setting in l10n.yaml and test a string containing an apostrophe after generation.

What you get back, and what Manuce does not do

You upload your source .arb file; you get the same file back, in the same format, ready to drop into the project:

• only the values change: indentation, key order, quotes, comments, line endings, encoding and BOM are preserved;
• @@locale is set to it;
• @ metadata keys are left alone, but their descriptions are used as context: a description such as ‘button that empties the basket’ helps choose Svuota rather than Cancella;
• not translated: keys, empty values, URLs, email addresses, numbers, colours, date formats, identifiers and anything marked as non-translatable;
• a report comes with the file: strings translated, strings left as they were and why.

The word count covers the values only, keys and tags excluded. Manuce does not touch your Dart code: it does not add it to supportedLocales or run flutter gen-l10n. Material widget labels (date picker buttons such as Annulla) are not in your .arb files; they come from the flutter_localizations package. Nor is this a sworn translation: if terms of use need certifying, you will need a sworn translator.

Preparing the file and checking the app in Italian

Before uploading:

• Start from one template file, usually app_en.arb, complete and up to date.
• Fill in descriptions for short or ambiguous strings: ‘Share’ (verb or noun?), ‘Open’ (action or state?). In Italian, Condividi and Condivisione, Apri and Aperto are not interchangeable.
• Avoid concatenation in Dart: 'Delete ' + item cannot agree in Italian. Use a message with a placeholder instead.
• Mark as non-translatable any product or plan names you keep as they are.

Once the file is back in the project as app_it.arb:

• add Locale('it') to supportedLocales and, for iOS, add Italian to the languages declared in Info.plist;
• run the app on a device set to Italian and go through the narrow spots: tabs, buttons, AppBar, dialogs;
• test plurals with 0, 1 and 2;
• check that dates and numbers go through intl with the it locale: 12 marzo 2025 (lower-case months), 1.234,50; these formats are not part of the translation;
• read the report: any string still in English is listed there with its reason.

In practice

1. Upload your template .arb file (for example app_en.arb): the quote appears straight away, based on the words in the values.
2. Choose Italian and a level, then read the free sample before paying.
3. Download the translated file, with @@locale set to it, and the report on strings left unchanged.
4. Save it as app_it.arb, run flutter gen-l10n and test the app on a device set to Italian.