nigp.org
Link authority for nigp.org (registrable domain: nigp.org) from the Common Crawl web graph: PageRank and harmonic centrality history since 2017, current scores, and the site's top backlink sources.
Web-graph authority (0-100)
Domain scores measure nigp.org 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 nigp.org. 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.
Homepage
What nigp.org presents on its own homepage: the page title, description, and the social share markup it publishes. Pulled from https://www.nigp.org.
| Title | NIGP: Public Procurement Education, Certification and Research |
|---|---|
| Description | NIGP is the leading institute for public procurement. Explore certification, training, research, and consulting for state and local agencies. |
| OG Title | NIGP: Public Procurement Education, Certification and Research |
| OG Description | NIGP is the leading institute for public procurement. Explore certification, training, research, and consulting for state and local agencies. |
| Twitter Title | NIGP: Public Procurement Education, Certification and Research |
| Twitter Card | https://s3.us-east-1.amazonaws.com/nigp-prod-media/assets/branding/nigp-logo-masthead.png |
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.
| OfficialNIGP | |
| national-institute-of-governmental-purchasing (business) | |
| Youtube | NIGP1 |
| Contact pages | https://www.nigp.org/contact-us |
|---|---|
| Emails | rlevine@nigp.org |
| Phones |
+17037368900 +18003676447 +17036352326 |
| Blog |
https://www.nigp.org/blog/category/learning-by-design https://www.nigp.org/blog https://www.nigp.org/blog/category/forum-stories |
Structured data (JSON-LD)
The schema.org markup this homepage publishes: the machine-readable identity search engines and AI systems read. Types found: Organization, WebSite, FAQPage.
JSON-LD block (841 bytes)
{"@context":"https:\/\/schema.org","@type":"Organization","name":"NIGP: The Institute for Public Procurement","url":"https:\/\/www.nigp.org","logo":"https:\/\/www.nigp.org\/logo.png","description":"NIGP is the leading professional association for public procurement professionals, providing education, certification, research, and consulting to over 19,000 members across North America.","foundingDate":"1944","numberOfEmployees":"19000","address":{"@type":"PostalAddress","streetAddress":"12007 Sunrise Valley Drive, Suite 110","addressLocality":"Reston","addressRegion":"VA","postalCode":"20191","addressCountry":"US"},"contactPoint":{"@type":"ContactPoint","telephone":"703-736-8900","contactType":"customer service"},"sameAs":["https:\/\/www.linkedin.com\/company\/nigp","https:\/\/www.facebook.com\/nigp","https:\/\/twitter.com\/nigp"]}JSON-LD block (241 bytes)
{"@context":"https:\/\/schema.org","@type":"WebSite","url":"https:\/\/www.nigp.org","potentialAction":{"@type":"SearchAction","target":"https:\/\/www.nigp.org\/search?q={search_term_string}","query-input":"required name=search_term_string"}}JSON-LD block (2,442 bytes)
{"@context":"https:\/\/schema.org","@type":"FAQPage","mainEntity":[{"@type":"Question","name":"What is NIGP?","acceptedAnswer":{"@type":"Answer","text":"NIGP: The Institute for Public Procurement is the leading professional association for public procurement professionals in North America. Founded in 1944, NIGP provides education, certification, research, consulting, and community to over 19,000 members across more than 2,400 state and local agencies."}},{"@type":"Question","name":"What is public procurement?","acceptedAnswer":{"@type":"Answer","text":"Public procurement is the process by which government agencies and public sector organizations purchase goods, services, and works using taxpayer funds. Public procurement professionals are responsible for ensuring these purchases deliver value, comply with regulations, and serve the communities they support."}},{"@type":"Question","name":"What certifications does NIGP offer?","acceptedAnswer":{"@type":"Answer","text":"NIGP offers the NIGP Certified Procurement Professional (NIGP-CPP) certification, which is the only certification promoted, managed, and administered by NIGP. It is ANAB accredited and recognized as the benchmark for competency in public procurement."}},{"@type":"Question","name":"Who can join NIGP?","acceptedAnswer":{"@type":"Answer","text":"NIGP membership is open to public procurement professionals working in state and local government, school districts, hospital systems, counties, townships, and other public agencies, as well as individuals and organizations that support the public procurement profession."}},{"@type":"Question","name":"What is the NIGP Forum?","acceptedAnswer":{"@type":"Answer","text":"The NIGP Forum is the premier annual conference for public procurement professionals, bringing together thousands of practitioners, industry leaders, and suppliers for education, networking, and professional development. The 2026 Forum takes place August 23 to 26 in Columbus, Ohio."}},{"@type":"Question","name":"What is cooperative purchasing?","acceptedAnswer":{"@type":"Answer","text":"Cooperative purchasing is a procurement strategy that allows government agencies to purchase goods and services through contracts established by other public agencies or cooperative organizations, saving time and taxpayer dollars. NIGP provides resources, research, and education to help agencies implement effective cooperative purchasing programs."}}]}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 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 nigp.org and domain-level for nigp.org 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.
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 nigp.org (including its subdomains), ranked by the linker's PageRank. The table shows the top 458; the download carries the full stored list (up to 10,000 linkers) as JSON. Click a linker for its own site profile.
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 nigp.org specifically, ranked by the linker's PageRank. The table shows the top 18; the download carries the full stored list (up to 10,000 linkers) as JSON. Click a linker for its own site profile.
| Linking Site | Linker PageRank | Linker Harmonic Centrality |
|---|---|---|
| dltech.forum | 16 | 11 |
| www.rmgpa.org | 15 | 13 |
| www.kppanigp.org | 13 | 13 |
| www.tappnews.com | 11 | 13 |
| kppanigp.org | 10 | 13 |
| magppa.org | 10 | 8 |
| www.nmppa.org | 8 | 13 |
| factmags.com | 8 | 13 |
| www.nigpsefl.org | 7 | 11 |
| kappp.org | 6 | 9 |
| rmgpa.clubexpress.com | 5 | 13 |
| rmgpa.org | 5 | 9 |
| nmppa.org | 4 | 8 |
| mrsupplychain.com | 3 | 13 |
| mappofnigp.org | 0 | 12 |
| tappnews.com | 0 | 0 |
| gpag.net | 0 | 0 |
| www.gcagpo.org | 0 | 0 |