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Site Information

hdtech.com

Link authority for hdtech.com (registrable domain: hdtech.com) from the Common Crawl web graph: PageRank and harmonic centrality history since 2017, current scores, and the site's top backlink sources.

7Domain PageRank
14Host Backlinks
22Domain Backlinks
Link authority data (PageRank, harmonic centrality) and backlinks come from the Common Crawl web graph.
hdtech_com.profile
Current Scores

Web-graph authority (0-100)

Domain scores measure hdtech.com as a whole: every subdomain's links rolled up into one node of Common Crawl's domain-level web graph. Host scores measure the exact hostname hdtech.com. WWW scores cover the www variant of that hostname, which the graph tracks as its own entry since January 2026 (before that, www and bare host were merged). A big gap between domain and host usually means the domain's authority lives on other subdomains. PageRank is link-endorsement authority: how much weight the sites linking here carry themselves. Harmonic centrality measures reach: how close this site sits to the rest of the web when following links, which favors broadly connected sites over ones boosted by a few heavy linkers. All are normalized 0 to 100 within each crawl snapshot; a dash means that series does not exist for this site.

7
Domain PageRank
3
Host PageRank
-
WWW PageRank
95
Domain Harmonic Centrality
94
Host Harmonic Centrality
-
WWW Harmonic Centrality
Site Intelligence

Homepage

What hdtech.com presents on its own homepage: the page title, description, and the social share markup it publishes. Pulled from https://hdtech.com.

TitleManaged IT Services Orange County & Los Angeles | HD Tech
DescriptionManaged IT & cybersecurity for Orange County and LA businesses since 1995. 24/7 monitoring, sub-4-minute response, flat-rate pricing. Free IT audit.
OG TitleHD Tech | Your Cyber Lifeguard — Managed IT & Cybersecurity
OG DescriptionEnterprise-grade managed IT and cybersecurity for LA & Orange County businesses. Sub-4-minute response. 30 years trusted.
OG Site NameHD Tech
Twitter TitleHD Tech | Managed IT & Cybersecurity
Twitter Cardsummary_large_image
Site Intelligence

Social accounts and contact points

Where this site maintains a presence and every reachable route its homepage exposes: social accounts, contact pages, addresses, and content feeds.

Facebook hdtechnologies
Linkedin h-d-technologies (business)
Youtube UCVd32h5n2oEglVdX18UJp1Q (channel)
Instagram hdtechoc
Contact pages https://hdtech.com/contact
Emails info@hdtech.com
Phones 8775401684
Blog https://hdtech.com/blog
Site Intelligence

Structured data (JSON-LD)

The schema.org markup this homepage publishes: the machine-readable identity search engines and AI systems read. Types found: Organization, LocalBusiness, Person, FAQPage.

JSON-LD block (2,462 bytes)
{"@context":"https://schema.org","@graph":[{"@type":["Organization","LocalBusiness"],"@id":"https://www.hdtech.com/#organization","name":"HD Tech","url":"https://www.hdtech.com","logo":"https://www.hdtech.com/hdtech-logo-main.png","foundingDate":"1995","description":"HD Tech is a managed IT services provider and cybersecurity company serving Orange County and Los Angeles businesses since 1995. Flat-rate managed IT, 24/7 SOC monitoring, help desk support, compliance, and cybersecurity.","telephone":"+18775401684","email":"info@hdtech.com","address":{"@type":"PostalAddress","streetAddress":"322 Main Street, Suite 4","addressLocality":"Seal Beach","addressRegion":"CA","postalCode":"90740","addressCountry":"US"},"geo":{"@type":"GeoCoordinates","latitude":33.7415,"longitude":-118.1046},"openingHours":["Mo-Fr 08:00-18:00"],"openingHoursSpecification":[{"@type":"OpeningHoursSpecification","dayOfWeek":["Monday","Tuesday","Wednesday","Thursday","Friday"],"opens":"08:00","closes":"18:00"}],"areaServed":[{"@type":"City","name":"Seal Beach","containedInPlace":{"@type":"State","name":"California"}},{"@type":"City","name":"Orange County","sameAs":"https://en.wikipedia.org/wiki/Orange_County,_California"},{"@type":"City","name":"Los Angeles","sameAs":"https://en.wikipedia.org/wiki/Los_Angeles"},{"@type":"City","name":"Irvine"},{"@type":"City","name":"Anaheim"},{"@type":"City","name":"Santa Ana"},{"@type":"City","name":"Long Beach"},{"@type":"City","name":"Huntington Beach"}],"sameAs":["https://www.linkedin.com/company/hdtech","https://facebook.com/hdtechnologies","https://www.yelp.com/biz/hd-technologies-seal-beach"],"priceRange":"$$","aggregateRating":{"@type":"AggregateRating","ratingValue":"4.8","ratingCount":47,"bestRating":"5","worstRating":"1"},"contactPoint":{"@type":"ContactPoint","contactType":"Sales","telephone":"+18775401684","email":"info@hdtech.com","areaServed":["Orange County","Los Angeles","Southern California"]}},{"@type":"Person","@id":"https://www.hdtech.com/#tom-hermstad","name":"Tom Hermstad","jobTitle":"President & CMO","url":"https://www.hdtech.com/about/team","image":"https://www.hdtech.com/tom-hermstad.jpg","sameAs":["https://www.linkedin.com/in/tomhermstad","https://www.yelp.com/user_details?userid=tom-hermstad-seal-beach"],"worksFor":{"@type":"Organization","name":"HD Tech","url":"https://www.hdtech.com"},"expertise":["Managed IT Services","Cybersecurity","CMMC Compliance","MSP Leadership","IT Strategy"]}]}
JSON-LD block (2,131 bytes)
{"@context":"https://schema.org","@type":"FAQPage","mainEntity":[{"@type":"Question","name":"What does HD Tech do?","acceptedAnswer":{"@type":"Answer","text":"We provide enterprise-grade managed IT services and cybersecurity for businesses with 10-500+ employees. From 24/7 monitoring and help desk support to compliance, backup, and AI deployment — we handle your entire technology stack so you can focus on running your business."}},{"@type":"Question","name":"What industries does HD Tech specialize in?","acceptedAnswer":{"@type":"Answer","text":"We serve accounting firms, law firms, construction companies, and defense contractors — plus businesses across insurance, manufacturing, healthcare, and logistics. Each industry has unique compliance and security requirements, and we tailor our approach accordingly."}},{"@type":"Question","name":"How fast is your response time?","acceptedAnswer":{"@type":"Answer","text":"Our average response time is under 4 minutes. Every call is answered by a real, US-based expert — not a bot or overseas call center. When your business is down, seconds matter."}},{"@type":"Question","name":"Do you require long-term contracts?","acceptedAnswer":{"@type":"Answer","text":"No. We offer month-to-month agreements because we believe our service should earn your business every month. Most clients stay for 10+ years — not because they're locked in, but because the service speaks for itself."}},{"@type":"Question","name":"What is the Cyber Lifeguard Rescue Scan?","acceptedAnswer":{"@type":"Answer","text":"It's a free, 60-second AI-powered security assessment that checks your domain for breached credentials, email spoofing vulnerabilities, SSL issues, and compliance gaps. No software to install, no credentials needed — just enter your domain and see what hackers can see."}},{"@type":"Question","name":"Where is HD Tech located?","acceptedAnswer":{"@type":"Answer","text":"Our headquarters is at 322 Main Street, Suite 4, Seal Beach, CA 90740. We provide on-site support throughout Los Angeles and Orange County, with remote monitoring and support capabilities nationwide."}}]}
Web-Graph History

Authority over time

Every Common Crawl web-graph release since 2017, roughly quarterly. The domain series goes back to 2017; Common Crawl only began publishing the host-level graph in 2020, so host lines start there. Click a legend entry to show or hide that line. Flat lines are normal for established sites; watch for sustained rises or drops, which track real gains or losses in who links here.

A note on www: through the end of 2025 the source web graph merged www and non-www hostnames into the bare name, so one host line covers both. Starting in January 2026 the graph splits them into separate entries, which is why www can carry its own scores going forward.

Backlink Data

Backlink counts

Unique linking domains seen in Common Crawl's link graphs. This is a different dataset than the 0-100 authority scores above: these are raw counts, host-level for hdtech.com and domain-level for hdtech.com with all its subdomains combined. Common Crawl covers a large sample of the web, not all of it, so treat counts as comparable between sites rather than absolute totals.

14
Host Backlinks
22
Domain Backlinks
Backlink Data

Top backlinks in the domain graph

Common Crawl publishes two link graphs. The DOMAIN graph connects whole domains: every link from any page of one domain to any page of another. This table shows the highest-authority domains linking to hdtech.com (including its subdomains), ranked by the linker's PageRank. The table shows the top 22; the download carries the full stored list (up to 10,000 linkers) as JSON. Click a linker for its own site profile.

Download domain backlinks (.json)

Backlink Data

Top backlinks in the host graph

The HOST graph connects exact hostnames, so subdomains count separately. This table shows the highest-authority hosts linking to hdtech.com specifically, ranked by the linker's PageRank. The table shows the top 14; the download carries the full stored list (up to 10,000 linkers) as JSON. Click a linker for its own site profile.

Download host backlinks (.json)