Free technical SEO tools — the pre-flight checklist
Schema markup, sitemaps, robots.txt, redirects, canonical tags, hreflang — the plumbing that decides whether your site gets crawled correctly in the first place. 26 tools to generate, validate, and inspect every technical signal Google reads.
Schema & structured data
5 tools in this sub-group
Schema Markup
JSON-LD for rich snippets
FAQ Schema Generator
FAQPage JSON-LD for rich results
Product Schema
Product JSON-LD with offers
Breadcrumb Schema
BreadcrumbList JSON-LD
JSON-LD Validator
Validate structured data
Crawlers & indexing
9 tools in this sub-group
Robots.txt Generator
Build crawler rules visually
Robots.txt Tester
Is this URL allowed?
Sitemap Generator
Build valid sitemap.xml
XML Sitemap Parser
Analyze sitemap structure & issues
Sitemap Validator
Validate sitemap.xml
Canonical Tag
rel=canonical link tag
Noindex Checker
Find all indexability directives
hreflang Generator
Multi-region language tags
Redirect Rule Generator
.htaccess, Nginx, Next.js & more
Meta tags & social
4 tools in this sub-group
Dev utilities
8 tools in this sub-group
HTML Minifier
Strip whitespace & comments
CSS Minifier
Remove whitespace & comments from CSS
JSON Formatter
Format, validate & minify JSON
Text Encoder / Decoder
Base64, URL, HTML entities, Hex
URL Parser
Break down any URL
Link Extractor
Pull URLs & emails from text
Color Contrast Checker
WCAG AA/AAA ratio in real time
UTM Link Builder
Campaign tracking URLs
Frequently Asked
Technical SEO questions, answered factually.
- Which schema.org types does Google actually use for rich results?
- Google's rich results documentation (developers.google.com/search/docs/appearance/structured-data) lists ~30 supported types. The highest-value ones: Article, Product, Recipe, Event, FAQPage, HowTo, Organization, LocalBusiness, VideoObject, Breadcrumb. Each has required and recommended properties — our Schema Markup Generator only outputs the required set by default and validates against schema.org's JSON-LD spec.
- What goes in a properly-formed robots.txt?
- Per RFC 9309 (2022, which formalized robots.txt), the file must be at /robots.txt, served as text/plain, UTF-8 encoded, and under 500KiB. Google specifically honors: User-agent, Allow, Disallow, Sitemap. The Crawl-delay directive is ignored by Google (use Search Console crawl rate instead). Our Robots.txt Tester simulates Googlebot against your rules using the same regex rules Google publishes.
- How do I implement hreflang correctly across regional versions?
- Every regional page must reference all other regional pages including itself, using bidirectional x-default for the fallback. Codes are IETF BCP 47 (ISO 639-1 language + ISO 3166-1 country, e.g., en-US). Google treats unreciprocated hreflang as invalid and ignores it entirely. Our hreflang Generator produces a clean matrix for any set of URLs + region codes and emits both <link> and HTTP-header formats.
- What HTTP headers affect SEO?
- Six headers matter: (1) X-Robots-Tag for indexing directives; (2) Content-Type for MIME sniffing; (3) Cache-Control for crawl efficiency + Core Web Vitals (TTFB feeds LCP); (4) Strict-Transport-Security (HSTS, RFC 6797) for the HTTPS signal; (5) Content-Security-Policy for XSS protection; (6) Vary for cache key correctness with Accept-Language. Our HTTP Headers Analyzer grades all six plus legacy X-Frame-Options and Referrer-Policy.
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