Localization gap finder

i18n JSON Compare

Use a source locale and a translated locale to find missing translation keys, obsolete extra keys, empty values, and value-type mismatches before release.

No upload Free to use Works on mobile

Data tool

i18n JSON Compare

Options

Localization gaps

0 results

How to use i18n JSON Compare

1

Paste both locale files

Use the complete source-language file and one translation file.

2

Compare flattened keys

Nested objects are converted into matching key paths.

3

Fix release blockers

Review missing, extra, empty, and type-mismatched translation entries.

Common uses

Release QA

Catch missing interface strings before deployment.

Translation cleanup

Identify obsolete keys that can be removed.

Framework migrations

Compare locale files after restructuring translation namespaces.

i18n JSON Compare FAQ

Is i18n JSON Compare free to use? +

Yes. i18n JSON Compare is free to use without an account or usage meter.

Is my data uploaded or stored? +

No. The processing for this tool runs locally in your browser. Entered content is not sent to our server.

Does it translate missing values? +

No. It focuses on deterministic structural QA so teams can send an accurate missing-key list to translators.

Keep working

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