Tutorial

Localize Your E‑Commerce Prices for Japan with SiteLocaleAI

Published May 19, 2026

Localize Your E‑Commerce Prices for Japan with SiteLocaleAI

Localizing Prices for Japan with SiteLocaleAI

Expanding your e‑commerce store into Japan can be a game‑changer, but it also brings a set of challenges: language barriers, currency conversion, and the subtle art of price presentation. Japanese shoppers are especially sensitive to price perception, and psychological rounding—the practice of ending prices on numbers that feel “right” (e.g., ¥1,980 instead of ¥2,000)—can boost conversion rates.

SiteLocaleAI’s self‑hosted JavaScript library makes this process painless. In this tutorial we’ll walk through:

  1. Adding the drop‑in script to any front‑end framework.
  2. Configuring price localization with psychological rounding for JPY.
  3. Using the CLI to pre‑render translated pages for SEO.
  4. Deploying the solution on a typical static‑site or WordPress setup.

1. Install the Library

SiteLocaleAI works anywhere—React, Vue, plain HTML, WordPress, Shopify, you name it. The only requirement is an LLM API key (Claude, GPT‑4o‑mini, etc.) that will power the translation.

<!-- Load the CDN version (no npm needed) -->
<script src="https://cdn.sitelocaleai.com/locale.js"></script>
<script>
  const locale = new SiteLocaleAI({
    apiKey: 'YOUR_LLM_API_KEY', // replace with your key
    targetLang: 'ja',            // Japanese
    priceConfig: {
      currency: 'JPY',
      rounding: 'psychological' // enable charm rounding
    }
  });

  // Translate the whole page once it loads
  locale.translatePage();
</script>

If you prefer a module bundler, the same configuration works with import:

import SiteLocaleAI from 'sitelocaleai';

const locale = new SiteLocaleAI({
  apiKey: process.env.LLM_API_KEY,
  targetLang: 'ja',
  priceConfig: { currency: 'JPY', rounding: 'psychological' }
});

locale.translatePage();

Tip: The library is framework‑agnostic, so you can place the script tag in the <head> of any HTML template, or enqueue it via WordPress’s wp_enqueue_script hook.

2. Price Localization with Psychological Rounding

Japanese prices are usually displayed without decimal places, and the “charm” effect comes from ending prices in ¥9 or ¥99. SiteLocaleAI handles this automatically when you enable the rounding: 'psychological' option.

Inside your product template, mark price elements with the data-price attribute:

<span class="price" data-price="19.99">$19.99</span>

When translatePage() runs, the library:
1. Detects the data-price value (USD in this example).
2. Calls the LLM to convert the amount to JPY using the latest exchange rate.
3. Applies psychological rounding (e.g., ¥2,980).
4. Replaces the inner text with the localized price.

You can also format the price manually if you need custom logic:

locale.formatPrice = (usd) => {
  const jpy = usd * 150; // static rate for demo; real implementation fetches live rates
  const rounded = Math.round(jpy / 10) * 10 - 20; // example charm rounding
  return `¥${rounded.toLocaleString()}`;
};

For a deeper dive, see the official docs: https://sitelocaleai.com/docs/price-localization.

3. SEO‑Friendly Pre‑Rendering

Search engines still struggle with client‑side rendered content. SiteLocaleAI ships a CLI that pre‑renders translated pages so crawlers receive fully translated HTML.

# Install the CLI globally (optional)
npm i -g @sitelocaleai/cli

# Pre‑render the Japanese version of your site
npx sitelocaleai pre-render \
  --lang ja \
  --output ./dist/ja \
  --api-key $LLM_API_KEY

The command:
- Crawls your source directory.
- Sends each page’s text to the LLM for translation.
- Generates a static copy in ./dist/ja with all prices already localized.

Deploy the generated folder to your CDN or static‑site host. Google and Bing will now index the Japanese pages, giving you a solid international SEO boost.

For more CLI options, check the quick‑start guide: https://sitelocaleai.com/docs/quickstart.

4. WordPress Integration (No Node Required)

If your store runs on WordPress, you can skip the npm step entirely. The official SiteLocaleAI plugin adds a settings page where you paste your LLM key, select target languages, and enable price rounding.

  1. Install the plugin from the WordPress admin → Plugins → Add New → Search “SiteLocaleAI”.
  2. Activate and go to Settings → SiteLocaleAI.
  3. Set Target Language to Japanese (ja) and enable Psychological Rounding.
  4. Save. The plugin injects the script automatically on every front‑end page.

All product prices wrapped with data-price will be transformed on the fly, and the plugin also provides a SEO Pre‑Render button that runs the CLI on the server (via a simple PHP wrapper).

5. Testing & Validation

After deployment, verify three things:

✅ Check
1 The UI displays Japanese text and ¥ prices with charm rounding (e.g., ¥1,980).
2 The page source (view‑source) contains the translated HTML, not just a script tag.
3 Google Search Console shows the new /ja/ URLs indexed without crawl errors.

Use Chrome DevTools → Network → XHR to ensure the LLM calls are made only once per page load.

6. Going Live

Once you’re satisfied with the preview, push the generated /ja/ folder to your production CDN. Update your sitemap to include the new language URLs, and submit it to Google Search Console.

<url>
  <loc>https://yourstore.com/ja/</loc>
  <changefreq>weekly</changefreq>
  <priority>0.8</priority>
</url>

That’s it—your store is now fully localized for Japanese shoppers, with prices that feel natural and a SEO‑friendly architecture that drives organic traffic.

🎯 Ready to Expand?

International growth shouldn’t be a technical nightmare. With SiteLocaleAI you get a drop‑in, self‑hosted solution that handles translation, price rounding, and SEO pre‑rendering in minutes.

👉 Try SiteLocaleAI today and watch your Japanese conversion rates climb. Visit https://sitelocaleai.com to start your free trial.

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