i18n JSON Key Checker — Missing & Extra Translation Keys
Compare two JSON string dictionaries locally. Find missing or extra translation keys, blank strings and structure conflicts with exact JSON Pointer paths, without uploading locale files.
Enabling local controls…
1. Add two locale dictionaries
Browser-memory only: no upload, storage or URL state. Reports omit translation values, but key names may reveal project information.
Supported format and limits
Root object, nested objects and string values only. Arrays, null, numbers, booleans, duplicate keys and invalid Unicode are refused. Exact JSON structure: a.b is not a → b. No case or whitespace changes. One leading BOM is removed with a notice.
Each input: 1 MiB UTF-8, 100 levels, 50,000 nodes, 20,000 strings; paths: 4096 bytes. Five-second timeout, complete report: 8 MiB, copy: 1 MiB. Strict file decoding; originals are never overwritten.
2. Key check results
Add two dictionaries or load the sample, then run the check.
String-dictionary structure only, not translation quality. Plurals, fallback, placeholders and ICU are not validated; extra keys may be intentional.
How to use this tool
Paste or choose two UTF-8 dictionaries and check translation keys. Review issue counts, filter and page through exact paths, then copy missing paths or download the complete value-free JSON report. Values may be previewed on demand.
When not to use it
String dictionaries only, not a translation-quality or framework validator. No arrays, null, numbers or booleans; no automatic key edits, dot-key aliases, plural/fallback/ICU or placeholder validation. Extra keys can be intentional and matching text can be correct.
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