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Ardam
Ardam

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I built a tool to translate JSON i18n files without breaking anything

A few weeks ago I ran into a small but frustrating problem.

I was using AI to translate JSON i18n files. It worked… until it didn’t.

Keys would get changed
Placeholders like {name} or %d would break
Sometimes the JSON wouldn’t even parse

Every time, I had to manually fix the output before I could use it.

That defeats the whole point.

The real issue

AI is great at generating text, but it doesn’t respect strict structure.

And i18n files depend on structure:

keys must stay identical
placeholders must remain untouched
formatting must be valid

If any of those break, your app breaks.

What I built

I built a simple tool that does one thing:

Translate JSON i18n files without breaking anything

You upload a file, choose a language, and get back:

same keys
placeholders preserved
valid JSON
production-ready output

No cleanup needed.

Where most tools fail

The interesting part wasn’t building it, it was testing it properly.

I tested against real-world cases:

deeply nested objects
arrays
mixed placeholders ({name}, %d, {count})
UI strings, emails, notifications

This is where most approaches fail quietly.

Why I made it

I didn’t want a smarter translator.

I wanted a safer one.

Something you can actually trust in a production workflow without double-checking every line.

Would you use this?

I’m trying to understand:

Is this something you’d actually use in your workflow?
How are you currently handling JSON translations?
What would make this a must-have tool for you?
Try it

If you want to test it:

https://localizejson.lovable.app

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