How to Translate .po Files Without Breaking Code Variables (%s, HTML)

It starts with a simple task: you translate your WordPress theme into Spanish. You upload the .mo file, refresh your site, and...

Fatal error: Uncaught ArgumentCountError: Too few arguments to function sprintf()...

Or perhaps your site loads, but the layout is shattered because a closing </div> tag got translated into </ div>.

This is the number one fear of every developer working with localization. When you use generic translation tools (like Google Translate or basic AI wrappers) on technical .po files, they don't treat code differently from text. They try to "translate" your variables, and in doing so, they break your website.

In this guide, we’ll explain exactly why this happens and how to ensure 100% code safety in your automated translations.

The Anatomy of a Disaster: Why %s Breaks Sites

WordPress uses the Gettext system and PHP functions like sprintf() to handle dynamic text.

For example, you might have a string like this: msgid "Search results for %s"

The %s is a placeholder variable where PHP will insert the user's search query.

How Generic AI Gets It Wrong

When you feed this string into a standard Large Language Model (LLM) or translation API, it sees %s as just another weird word. It might try to fix the grammar or punctuation around it.

Here are the most common syntax errors we see:

1. The Added Space:

   • Original: Hello %s
   • Bad Translation: Hola % s
   • Result: PHP looks for %s, but it sees % s. The variable fails to load, often causing a fatal error.

2. The HTML Hallucination:

   • Original: Click <strong>here</strong> to login.
   • Bad Translation: Haga clic <strong>aquí</ strong> para iniciar sesión.
   • Result: The AI added a space inside the closing tag </ strong>. Your CSS breaks, and the rest of the page turns bold.

3. The Argument Swap:

   • Original: Page %1$s of %2$s
   • Bad Translation: Página %2$s de %1$s
   • Result: The AI decided the sentence sounded better if the numbers were swapped. Now your pagination says "Page 10 of 1".

The "Manual Fix" Trap

Most developers try to solve this by manually reviewing the file. If you have a small plugin with 50 strings, that’s fine. But if you are translating a WooCommerce store with 5,000 strings?

Scanning 5,000 lines of code for a single missing semicolon or an extra space inside a %s variable is impossible. It takes hours, and human eyes will inevitably miss something.

Regex (Regular Expressions) scripts can help verify presence, but they rarely catch context-specific reordering issues or subtle HTML attribute corruption.

The Solution: "Syntax Locking"

The only way to safely translate a .po file is to prevent the AI from ever touching the code in the first place. This requires a process called Syntax Locking.

This is the core technology behind SimplePoTranslate.

Unlike generic tools, we don't just dump text into an AI. We parse the Gettext structure first. Here is how our "Safe Mode" works:

1. Analysis: We scan your .po file and identify every variable (%s, %d), every positional argument (%1$s), and every HTML tag (<br/>, <span>).
2. Extraction & Locking: We temporarily remove these elements from the string and replace them with immutable tokens.
   • Input: Hello <strong>%s</strong>
   • What the AI sees: Hello [TOKEN_1][TOKEN_2]
3. Translation: The AI translates the text "Hello" to "Hola", but it cannot physically alter [TOKEN_1] or [TOKEN_2] because they are locked.
4. Reconstruction: We re-insert the original code into the translated string exactly where it belongs.

The Result: Zero Broken Sites

Because the AI never interacts with the actual %s or HTML characters, it is mathematically impossible for the translation engine to add a space inside a variable or corrupt a tag.

We even handle complex Pluralization rules (msgid_plural) for languages like Russian or Polish, ensuring the correct variable is used for the correct count.

Stop Gambling with Your Code

You shouldn't have to cross your fingers every time you upload a language file. Localization should be about reaching new customers, not debugging PHP errors.

SimplePoTranslate is the safest, most advanced cloud-based tool for developers who care about code integrity.

• Cloud-Based: No plugins to install.
• Context-Aware: Uses Gemini/GPT-4 class AI for natural phrasing.
• Syntax Locked: Guaranteed protection for your variables.

Ready to translate without the headache? Start for free at SimplePoTranslate.com