More and more companies are considering an English version of their website after overseas customers, job seekers, and business partners ask, "Don't you have an English page?" There are four main options, and they differ significantly in initial cost, monthly maintenance, and whether your English pages can be found on Google and AI search. In this article, we compare each method using the same criteria.
1. Hire a translation agency to build a separate English site
This is the most traditional approach. You hand your source text to a translation agency and have a web production company build the English pages. The finished quality is high and you have full design freedom, but costs are charged per page, and every time you update your Japanese site, the English version must also be revised by hand. Updates often fall behind, leaving only the English version with outdated information.
| Best suited for | Companies with a small number of pages that rarely change, or that only want to translate the company profile and business overview sections of their corporate site into English. |
|---|---|
| Estimated cost | Translation costs several thousand to tens of thousands of yen per page, with production fees charged separately. The same costs recur with every update. |
| SEO | Because these are standalone HTML pages, they are ideal for search engines. However, hreflang configuration must be requested from the production company. |
2. Use a multilingual CMS plugin (such as WPML or Polylang for WordPress)
If you use WordPress, plugins such as WPML or Polylang let you manage posts for each language. Language versions are added within your site on the assumption that you enter the translations yourself (or connect a machine translation service). This approach feels familiar to companies that run their own CMS, but it involves work across the entire site, such as keeping plugins updated and compatible, ensuring theme support, and managing the impact on page speed. Website builders such as STUDIO, Wix, and Jimdo either do not support plugins or offer only limited functionality.
| Best suited for | Companies that run WordPress in-house and have staff who can manage translated text. |
|---|---|
| Estimated cost | Plugin licenses cost several thousand to tens of thousands of yen per year, with translation work charged separately. Setup and maintenance are often outsourced to a production company. |
| SEO | Good, depending on configuration. The plugin outputs language-specific URLs and hreflang tags. |
3. Install a JavaScript tag-based translation tool
With this method, you paste a single line of script tag into your site, and text is replaced with the translated language in the visitor's browser. It is easy to implement and enables multilingual display without changing your site. The point to watch is how search engines handle it. Because most tools, as a rule, "replace text in the browser," the HTML received by Google and AI crawlers may remain in Japanese. Some tools offer plans that provide language-specific URLs for SEO, so check before signing up whether your English pages will actually appear in English-language searches.
| Best suited for | Companies for which it is enough that visitors can read the site in multiple languages, and that do not prioritize search traffic. |
|---|---|
| Estimated cost | Mainly monthly subscriptions, varying by number of languages and page views. |
| SEO | Depends on the tool and plan. With a setup that only replaces text in the browser, your pages will not appear in English-language searches. |
4. Serve translated HTML on a separate subdomain
This method retrieves the public pages of your Japanese site, translates them, and serves the translated HTML pages on a separate subdomain such as global.example.co.jp/en/ . Your Japanese site remains completely untouched, and you can go live simply by adding one CNAME record to your DNS. Because each language page is returned from the server as translated HTML, crawlers from Google, Bing, and AI search engines can read it as is. When you update your Japanese site, only the changed pages are automatically retranslated. Sotomuke uses this method.
| Best suited for | Companies on any CMS, including WordPress, STUDIO, and Wix, that want English pages discoverable in search without modifying their site, and sites that are continually updated. |
|---|---|
| Estimated cost | With Sotomuke, 100 pages in 3 languages costs ¥4,980 per month (excluding tax), with no setup fee. |
| SEO | Language-specific URLs, canonical tags, hreflang tags, and sitemaps are generated automatically, and even Search Console registration is automated. |
Comparison table
| Translation agency + separate site | CMS plugin | JS tag | Separate delivery of translated HTML | |
|---|---|---|---|---|
| Changes to your site | New build | Plugin installation and theme compatibility | One line of tag code | None (1 DNS record) |
| When the Japanese site is updated | Applied manually | Manual or via integration | Automatic | Automatic (only changes are retranslated) |
| Readability for search engines and AI | ◎ | ◎ (depending on settings) | △ (depending on setup) | ◎ |
| Editing translations | Request from your web agency | Edit in the CMS | Edit in the dashboard | Edit and lock sentence by sentence in the dashboard |
| Initial cost | High | in | Low | None |
How to decide
- If you want to appear in English-language searches, choose a method where English pages are "returned from the server as English HTML" (1, 2, 4). For the JS tag type, check whether your plan can output language-specific URLs.
- If you will keep updating your Japanese site, you need a method that applies changes automatically (3, 4); otherwise the English version will be left behind.
- If you don't want to modify your site, or your CMS is STUDIO or Wix, a method that requires no work on the site side (3, 4) is the practical choice.
- If you want consistent proper nouns and phrasing, check whether a glossary and sentence-level editing are available.
If you want to offer not only English but also Chinese (Simplified and Traditional), Korean, and Vietnamese at the same time, a model where costs don't increase with each language is cheaper in the long run. Our approach for inbound visitors is summarized in Multilingual Websites for Attracting Inbound Visitors. For how to communicate languages to search engines, see What Is hreflang?.
Try it with Sotomuke
Just paste the URL of your Japanese website, and we'll create a free translated preview of your homepage. No CMS modifications or tag installation required. Publishing starts at ¥4,980 per month, with no minimum contract period.