SEO Tools
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These are the tools that produce the parts of a site a search engine reads rather than the parts a visitor sees: the meta tags in the head, the structured data that earns a rich result, the robots.txt and sitemap.xml at the root, and the hreflang cluster that tells Google which language version to serve to whom. All of them are files or tags you write once and then forget, which is exactly why they are so often wrong.
Start from what you are shipping. A new page needs a meta tag generator for its title, description and Open Graph block, and the Open Graph preview to see how that block renders before you post the link anywhere. A new site needs a robots.txt file and an XML sitemap. A site that has just changed its URLs needs 301 redirects, which are what carry the ranking of the old address to the new one. A site in more than one language needs hreflang tags. And any page competing for a rich result needs schema markup. Two of these look outward rather than at your own markup: the backlink finder reports who already links to a domain, and the content analyzer reads a page the way a ranking system does, counting the things a title tag and a word count cannot tell you.
SEO tools by where the output goes
| Tool | Where the output goes | What it controls |
|---|---|---|
| Meta Tag Generator | The head of one page | Title, description, Open Graph, Twitter Card |
| Open Graph Preview | Nothing; it reads a page | How a shared link looks on each platform |
| Schema Markup Generator | A script tag in the head | Eligibility for rich results |
| Hreflang Generator | Head, sitemap or HTTP header | Which language version is served where |
| XML Sitemap Generator | sitemap.xml at the site root | Which URLs you are asking to have crawled |
| Robots.txt Generator | robots.txt at the site root | Which paths crawlers may request |
| AI Scan | Nothing; it grades a site | llms.txt, AI bot access, structured data, semantics |
| Domain Search | Nothing; it queries registries | Whether a name is available across TLDs |
| htaccess Redirect Generator | An .htaccess file on an Apache server | Which old URLs point at which new ones |
The tags that have to agree with each other
Most technical SEO bugs are not a missing tag but two tags contradicting one another, and search engines resolve the contradiction by ignoring both. A canonical pointing at one URL while the sitemap lists another is the common case. hreflang has a stricter version of the same rule: every annotation must be reciprocal, so if the English page points at the German one, the German one has to point back, and both have to point at themselves. A one-way hreflang cluster is discarded entirely rather than partially honoured, which is why the hreflang generator emits the full matrix instead of a single tag.
The x-default value is the other half people skip. It names the page to serve when no language in the cluster matches the visitor, which is a language selector or your primary market, and without it Google picks for you. Language codes follow ISO 639-1 and region codes ISO 3166-1 alpha-2, in that order, so en-GB is valid and GB-en is silently ignored.
The two files at the root of your site
robots.txt controls crawling, and only crawling. This is the single most costly misunderstanding in the field: a page blocked by Disallow can still be indexed and shown in results, because a crawler that is not allowed to fetch the page can still see other sites linking to it. Worse, blocking the page means the crawler never reads the noindex tag you put there to remove it. To keep something out of the index, allow the crawl and use noindex. To keep something off the server, use robots.txt. The Robots Exclusion Protocol was finally standardised as RFC 9309 in 2022, which also fixed the long-ambiguous precedence rule: the most specific matching rule wins, not the last one.
The sitemap generator enforces the sitemaps.org limits, which are 50,000 URLs and 50 MiB uncompressed per file. Past either, the file needs splitting and referencing from a sitemap index, and the tool warns rather than writing something a search console will reject. A sitemap is a suggestion about what exists and when it changed, not an instruction to index, and lastmod is the only field of the three that Google is on record as reading.
Structured data, and the crawlers that are not Google
Schema.org markup does not improve rankings on its own. What it does is make a page eligible for a rich result - the FAQ dropdown, the breadcrumb trail above a title, the star rating, the recipe card - and that eligibility is worth far more clickthrough than a position or two. Google recommends JSON-LD in a script tag over microdata attributes for a simple reason: it is one block you can generate and validate independently of the markup, rather than annotations threaded through the HTML.
The audience has widened since. Answer engines read the same structured data, and AI Scan grades a site on what they need: whether an llms.txt file exists, whether AI crawlers are allowed in robots.txt, whether the page carries structured data at all, and whether its HTML is semantic enough to survive being turned into passages. Blocking GPTBot or ClaudeBot has no effect on Googlebot, which reads a separate group in the same file, so the two decisions are independent. Every tool here runs client-side except the two that must reach the network: AI Scan fetches the site it grades, and Domain Search queries registries over RDAP with a WHOIS fallback.
Frequently asked questions
- Does robots.txt remove a page from Google?
- No. robots.txt stops a crawler from fetching a page, not from indexing it, so a blocked URL can still appear in results based on links pointing at it. Blocking it also means the crawler never sees a noindex tag on the page. To remove a page from the index, allow crawling and serve noindex; use robots.txt to save crawl budget, not to hide content.
- How many URLs can one XML sitemap contain?
- Up to 50,000 URLs and 50 MiB uncompressed, per the sitemaps.org protocol. Beyond either limit, split the file and list the parts in a sitemap index, which is itself subject to the same 50,000 entry cap. Most large sites split by content type anyway, since a per-section sitemap makes indexation problems visible in Search Console.
- Do I need hreflang tags if my site is only in English?
- Only if you serve different English pages to different regions, such as separate pages for en-GB and en-US pricing. A single English site for everyone needs no hreflang at all. Adding it for one page with no alternates does nothing, because hreflang describes a cluster and a cluster of one is not a cluster.
- Is JSON-LD better than microdata for schema markup?
- For most sites, yes. Google recommends JSON-LD, and it keeps the structured data as one self-contained block in the head rather than as attributes spread through the markup, which means you can regenerate or validate it without touching templates. Microdata remains valid and is still read; it is simply harder to maintain.
- How long should a meta description be?
- Between roughly 120 and 158 characters. Shorter wastes the space, and longer is truncated in most result layouts, though Google rewrites descriptions often enough that treating it as a click prompt rather than a ranking factor is the right posture. The meta tag generator counts as you type and flags both ends of the range.
- Does blocking AI crawlers hurt my Google rankings?
- No. GPTBot, ClaudeBot, PerplexityBot and Googlebot are separate user agents matched by separate groups in robots.txt, so disallowing the first three leaves Google crawling exactly as before. The real trade-off is different: blocking them also removes your site from the answers those assistants give, which is a source of referral traffic rather than a ranking signal.