Paste your base language and a translation (.strings, JSON or key = value) and Strings Checker compares the keys: what is missing in the translation, what is extra, and which values are empty. Find the gaps before they ship.
Missing in translation
Extra (not in base)
Empty values
Download & run
Paste both Put the base language in the left box and the translation in the right.
Compare Click Compare keys to see missing, extra and empty entries.
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Understands Apple .strings, JSON, and simple key = value lines. Everything runs in your browser.