Technical SEO services in Japan – a foundation search engines can read

What technical SEO covers

Search engines discover pages through links and sitemaps (crawling), process and store them (indexing), then match them to queries. Technical SEO makes sure nothing breaks along that path. The work usually covers:

• Crawling: robots.txt, XML sitemaps and internal links that lead to the pages you care about
• Indexing: stray noindex tags and correct status codes (200, 301, 404)
• Canonicalization: one URL per piece of content and sensible canonical tags
• Mobile parity: the phone version carries the same content and structured data as the desktop version
• Speed and structured data: page weight and the markup that shapes how you appear in results

None of this is visible on the screen. The most reliable starting point is Google Search Console: verify your site and open the Page indexing report to see which pages are left out and why.

Signs of hidden technical problems

If any of these sound familiar, check the technical side before you invest in more content.

• New pages still do not appear in search weeks after publishing
• Search Console lists many pages as "Crawled – currently not indexed" or "Duplicate"
• Searching your brand shows a mix of http and https, or www and non-www URLs
• Pages that used to rank disappeared after a site renewal
• Text or images from the desktop version are missing on mobile
• Filters and sorting in your online store create thousands of near-identical URLs

Our guide to crawled but not indexed pages explains each Search Console status and what to do about it. Write down the affected URLs as you go – it makes finding the cause much faster.

Finding and fixing duplicate content

Duplicate content means the same, or nearly the same, page is reachable at several URLs. It is usually a side effect of how the system works. Search engines then have to guess which URL represents the page, signals get split and the wrong URL may show up. Common sources:

• The same page opens on http and https, with and without www, with and without a trailing slash
• Links point to URLs with tracking parameters such as ?utm_source=
• Store filters, sort orders and color variants each get their own URL
• WordPress tag, category and date archives repeat the same post lists
• Shopify creates product URLs nested under collections (its default canonical points to the main product URL)

The basic fix is to pick one URL format and 301-redirect every other version to it. Where similar pages need to stay, a canonical tag names the preferred URL. Google treats canonicals as a strong hint, so keep internal links and sitemaps pointing to the same preferred URLs to make the signal clear. Thin tag pages can also be set to noindex.

What mobile-first indexing means for your site

Google now crawls mainly with its smartphone crawler and indexes and evaluates the mobile version of your pages. Content that exists only on desktop may simply not count. Check these points on the mobile version:

• Content parity: collapsed or hidden text and tables still exist in the mobile HTML
• Headings and images: the same heading structure and alt text as desktop
• Meta data: titles, descriptions and robots directives match
• Structured data: breadcrumb, product and FAQ markup is present on mobile too
• Lazy loading: images and text that load on scroll are still retrievable by search engines

A responsive site that serves one HTML to every device covers most of this automatically. Separate mobile sites or themes that strip content on phones deserve a closer look first. For speed metrics see improving Core Web Vitals, and for markup see structured data basics.

How to run a technical SEO project, in priority order

Trying to fix everything at once stalls most projects. Work from the highest impact down:

• Baseline: the Search Console indexing report, sitemap status and a full URL list from a crawler
• Critical blockers: noindex on key pages, robots.txt blocks, 404s and server errors
• Canonicalization: one URL format, 301 redirects, canonical tags, no redirect chains
• Mobile content: close the gaps with desktop and align structured data
• Speed and internal links: trim heavy images and scripts, link more to important pages
• After the fixes: request recrawls and follow the reports over several weeks

To get started quickly, have ready: view access to Search Console and GA4, login details for your CMS (WordPress, Shopify, BASE or other) and a list of URLs that worry you. Indexing changes take time, so log the date of each fix to compare before and after.

How UNANOBO handles technical SEO: a free demo of the fixed site

UNANOBO starts from your current site address. We review URL structure, canonicalization, mobile output and structured data, then build a free demo showing how the site looks and works once those issues are fixed. We separate what can be solved in your CMS settings from what needs rebuilding, so you can decide how far to go.

The process is free demo, feedback, launch, growth. The founder handles every project personally, from the first review to checking Search Console after launch, and everything runs by message in Japanese or English. Search Console and analytics stay in your name; you simply grant access.