When you update your source file, JTranslate compares it to the previous version and works out what changed. Each target language then shows how many keys need attention.
Added - keys that exist in the new source but didn't before. These need translating.
Modified - keys where the source value changed. For example, you updated "Welcome back" to "Welcome back, {name}". The existing translation might still be fine, or it might need updating.
Removed - keys that no longer exist in the source. These get cleaned up from your target files when you run a translation or cleanup.
Each target language has a diff page showing pending changes. You can filter by type (added, modified, removed) and search by key path or value.
For modified keys, you'll see the current source value alongside the existing translation. If the translation is still valid, you can mark it as OK - either for that language or across all languages at once.
Each language shows a coverage percentage. This is the proportion of source keys that have a matching translation. A language at 100% with no pending changes is fully up to date.