A technical SEO audit is the first thing to do with any new site, and refreshing it quarterly makes sense even for established projects. Unlike a content audit (which inspects copy, titles, keywords), the technical one answers a single question: "can search engines properly crawl and index this site?". If the answer is no, no amount of content work will help. This guide walks through the full 2026 checklist, with concrete commands and online SEO tools that automate each check.
1. Indexability and crawl access
Start with the basics: open robots.txt and confirm you haven't blocked critical sections. A common mistake is leaving Disallow: / over from staging. Verify the homepage HTML doesn't carry meta robots noindex. Open GSC and Yandex Webmaster: review the "Pages" coverage count. If you have 100 canonical pages but only 30 are indexed, that's a signal. GSC's "Pages" report shows reasons: noindex, duplicate canonical, soft 404, or crawl error. Webmaster has an analogous section with the same reason buckets. Site Metrics Tool runs periodic ranking checks with diagnostics: for each keyword we record the URL that actually showed in the SERP and compare it to the one you intended to rank — divergence is highlighted immediately.
2. Sitemap.xml and its freshness
The sitemap should live at /sitemap.xml and be declared in robots.txt via the Sitemap directive. Inspect it: every URL returns 200, no duplicates, no orphans, lastmod is real (not the same date across 10,000 URLs — that's the "generated by one cron, nobody watches" pattern). For large sites, split the sitemap into an index + per-section children (sitemap-blog.xml, sitemap-tools.xml). Google and Yandex recommend ≤ 50,000 URLs per file and ≤ 50 MB. The GSC submitted-to-indexed ratio should be > 80% — anything less means you're submitting URLs the engine declines to index. A clear signal to improve content quality or prune junk pages.
3. Site speed and Core Web Vitals
In 2026 Google grades a page on three metrics: LCP (Largest Contentful Paint, ≤ 2.5s), INP (Interaction to Next Paint, ≤ 200ms), CLS (Cumulative Layout Shift, ≤ 0.1). The source of truth is CrUX (Chrome User Experience Report) — what Google itself uses for ranking and what PageSpeed Insights surfaces. Lighthouse in DevTools is synthetic and tends to be twice as optimistic as the real numbers. Site Metrics Tool auto-pulls 75th-percentile CrUX metrics for the connected domain daily and tracks 30-day deltas. If LCP rose from 2.1 to 3.4, that's a clear "we shipped something heavy without a perf review" signal.
4. HTTPS, HSTS and redirect chains
The site must be fully HTTPS — no mixed content (http:// images or scripts). Check curl -I https://your-site.com for Strict-Transport-Security: max-age should be at least 6 months. Redirect chains are a sore spot. If /page redirects to /Page, then to /Page/, then to www.your-site.com/Page/, each hop adds 100–300ms on slow networks. Sitemaps should contain only final URLs, no redirects. Probe with curl -L -o /dev/null -w "%{url_effective} %{num_redirects}\n" https://your-site.com/page — the redirect count shouldn't exceed 1.
5. Structured data and rich snippets
JSON-LD is the de-facto standard for 2026 structured data. The minimum kit for most sites: Organization on the homepage (with logo and social), WebSite (for sitelinks searchbox), Article on blog pages, FAQPage wherever an FAQ lives, BreadcrumbList on inner pages. E-commerce adds Product with offers and ratings. SaaS adds SoftwareApplication. Site Metrics Tool's own landing uses SoftwareApplication + Organization + WebSite + FAQPage. Validate with Google's Rich Results Test and the Schema Markup Validator. JSON-LD errors don't penalise on their own, but Google stops rendering the rich snippet — and CTR drops 10–30%.
6. Mobile version
Google has fully switched to mobile-first indexing: a site is graded by how the mobile Googlebot sees it. Run Mobile-Friendly Test on your key templates: homepage, category, product, article. Minimum rules: viewport meta set, font-size ≥ 14px, interactive elements (buttons, links) at least 44×44px, no horizontal scroll. In 2026 touch-target spacing also matters — adjacent clickable elements must have at least 8px of whitespace. Failing this, real mobile users mistap, the page accumulates poor UX signals, and rankings dip.
7. Internal linking and orphan pages
Internal linking is an underused lever. Every page should receive at least 3–5 internal links from other pages. Orphan pages — those nobody links to from within the site — index slower and rank worse. The check is simple: pull the full URL list from the sitemap, pull every URL that appears as an href in any other page's HTML (Screaming Frog or Sitebulb work). The diff is your orphan set. Then decide: keep them (and add links from navigation or related blocks), or drop them (noindex or 410).
8. Canonical URLs and query parameters
Every page should declare rel="canonical" pointing to itself or the "primary" variant. If you have /product?color=red and /product?color=blue, both should point to /product so Google doesn't treat them as duplicates. Filter parameters (sort, page, utm_*) should usually canonicalise to the parameter-less URL. Exception — pagination: use rel="prev" / rel="next" (optional in 2026) or simply self-canonicalise each page. A common bug is a canonical pointing to http: in HTML served over https: → Google isn't sure which version to index, ping-pongs between them, and burns crawl budget for nothing.
9. Backlinks and spam links
Audit your link profile regularly: which domains link to you, at what toxicity. Yandex Webmaster's "External links" returns the full referring-domain list via API. Site Metrics Tool syncs this weekly and computes a toxicity_score per source from patterns: TLD reputation, manipulative anchors (exact-match commercial keyword), link density from one IP block, domain history. If 200 new links surface in a week from .info and .xyz with the anchor "cheap viagra", that's a competitor negative-SEO attack — and those domains belong in the disavow file.
10. Audit cadence
Run the full technical audit quarterly. Between audits, wire up automatic alerts on critical metrics: nginx 5xx errors above 1% per hour, LCP regression > 500ms, 10+ pages dropping from the index in a day, new errors in Search Console. This shifts reaction from "noticed a month later" to "knew about it in an hour". Site Metrics Tool configures these alerts automatically once you connect a project — you only need to confirm email notifications are enabled.
Frequently asked
How long does a full technical audit take?
For a typical site (5–50K pages) — 4 to 16 hours of SEO time plus 2–24 hours waiting for a crawler (Screaming Frog or similar). With an automated online SEO tool like Site Metrics Tool the baseline audit takes 30 minutes.
Do I need separate SEO audits for Yandex and Google?
Technically — no, requirements overlap 90%. Differences are content-side (Yandex weighs uniqueness; Google weighs authority) and regional (Yandex wants Schema/PostalAddress markup for local businesses). After the technical pass, run a separate keyword/content audit per engine.
What matters more — speed or content?
Content wins. But between two competitors with equal content, the faster site wins. The right sequence: bring content up to top-of-niche level first, then optimise speed. Not the other way round.
Does Site Metrics Tool run the full technical audit automatically?
The platform automates 70% of the checklist: indexation, speed via CrUX, link profile, ranking changes. The remaining 30% (detailed canonical analysis, schema, mobile rendering) still needs manual review — we provide SEO monitoring with alerts but not a visual render of every template.