Worked guide / localization release checker
Check translated JSON for missing keys and broken placeholders
A file can be valid JSON and still contain missing interface text or a changed placeholder. Use a small example to check the structure.
By Value Addition · 15 October 2026 · AI-assisted original guide
Two different checks
JSON parsing asks whether a file follows JSON syntax. A release comparison asks whether the translated file still has the keys and value types your source expects. Both checks can matter before integrating a language file.
A small fictional example
The source contains welcome: "Hello {name}" and items: "You have %d items". The target contains welcome: "Bonjour {user}" and omits items. Both can be valid JSON objects. The comparison should flag the changed placeholder name and the missing key. It cannot decide whether the French wording is good.
Try broken and clean inputs
Open the free Localization Release Checker. Choose Try a broken demo, then Check the translation. Inspect the paths and source/target excerpts. Next choose Try a clean demo and run the check again. A clean report means no issues were found by these supported rules; it is not a release certificate.
Prepare real files carefully
Use one source and one target, each up to 1 MiB in the free starter. Supported inputs are nested JSON or flat CSV with exactly key,value headers. Duplicate JSON keys are rejected, including keys expressed with equivalent Unicode escapes. Paths use JSON Pointer escaping, so a slash inside a key stays distinct from a nested path.
Separate blockers from review notes
Missing keys, changed types, empty target text and supported placeholder mismatches need review. Extra keys appear as warnings. Optional digit and text-length checks are advisories: a translated date, number format or longer phrase can be correct. Do not rewrite the translation just to remove an advisory.
Know which syntax needs another validator
This tool checks simple brace placeholders and common printf forms. ICU plural/select, dynamic widths, custom placeholders, PO, XLIFF and YAML need format-specific tooling. Unsupported syntax warns instead of getting a silent pass. Your existing build linter may already cover the checks you need.
When the batch edition fits
The free one-language check includes CSV and JSON reports. The optional $7 USD offline edition supports one source with up to twenty target files, 5 MiB per file, reusable rules and a report ZIP. Files are processed locally. Reports can contain private text snippets, so review them before sharing. No translation or language-quality assessment is provided. AI-assisted original software and guide by Value Addition. Support: shruti4thewin@gmail.com.
Try your supported task first
The free starter is useful on its own. The optional offline batch edition is $7 USD, one time. Check its limits before buying.