Sixready to useSEO tools, right now

1 · Title / description length check

Widths are counted in display units — search results truncate by pixel, so a raw character count understates how much room a title actually takes. Keep titles under 60 units and descriptions between 70 and 160; they’ll rarely be truncated.

2 · Internal link suggestions

Internal links are the cheapest effective SEO action there is: connect related pages so crawlers can move through the site and weight flows with them. Type a keyword and find the scenario pages you could link together, with copy-paste HTML.

3 · JSON-LD structured data check

Checks locally whether it parses and whether each @type carries its required fields (HowTo / WebPage / BreadcrumbList / Article / FAQPage / ItemList). No network calls. The rich results test is the final word.

4 · Pre-launch checklist

Go through it in order and tick everything before submitting for indexing. The first four decide whether you can be found; the last four decide whether people click once found.

1. 1
   robots.txt isn’t blocking the whole site.Open yourdomain/robots.txtand confirm there’s no Disallow: /. Crawlers re-read it on their own schedule, so changes aren’t instant.
2. 2
   sitemap.xml opens and every URL in it returns 200.This site’s sitemap is generated by scripts/seo-prerender.js — run it once more after adding pages.
3. 3
   Every page has a canonical pointing at itself.URLs with query strings (?step=3 and similar) canonical to the parameter-free page, so you don’t compete with yourself.
4. 4
   The page doesn’t scroll sideways on a phone.Set the viewport to width=device-width, initial-scale=1, keep text at 12px or more, and tap targets at 40px or more.
5. 5
   The title and description are unique to this page.Reusing one description site-wide tells search engines the pages are duplicates.
6. 6
   There’s structured data.HowTo for tutorials, FAQPage for Q&A, BreadcrumbList for breadcrumbs — this site’s pages already ship them.
7. 7
   Images have alt text and sane dimensions.An image without alt isn’t content, and an oversized one slows first paint, which hits rankings directly.
8. 8
   HTTPS works site-wide and HTTP redirects.An expired certificate is the most common and most overlooked cause of losing indexing.

For the full walkthrough, scripts and acceptance criteria included, open SEO Toolbox Site guide (5 steps): Pick the tool list: only what runs purely in the browser → Implement the tool pages (input → compute → output) → Give every tool a "next step" scenario page.

5 · Keyword density analysis

Paste some body text to check word frequency and density. Higher isn’t better — 1%–3% reads naturally, and forcing it past 5% starts to look like keyword stuffing. Chinese has no spaces, so Latin words are counted per word and Chinese characters one by one as an approximation; the target phrase is matched as a whole string, counted separately.

6 · UTM tracking-link builder

Attach utm_source / medium / campaign and similar parameters to a promo / share link, so later you can break it down in analytics: how much the conversions differ between visitors from WeChat, from search or from a given campaign. All building happens locally, nothing is uploaded.