What Is Moz?
Also known as: Moz Pro, Moz.com
Moz is an SEO software platform best known for originating Domain Authority (DA), providing link research, keyword research, rank tracking, and site auditing tools.
Last reviewed: 18 August 2026 · Reviewed by iNet Ventures Link Building Team
In plain English
Moz was one of the first SEO tools on the market, and it created Domain Authority — a 0-100 score that estimates how strong a website's backlink profile is. Today, Moz Pro offers a suite of SEO tools including keyword research, rank tracking, site audits, and backlink analysis. While Ahrefs and Semrush have grown larger, Moz remains widely used, and DA has become a standard metric that agencies and publishers reference when discussing link quality.
Technical definition
Moz is a commercial SEO platform built on the Moz Link Index, which crawls and stores backlink data from across the web. Its key tools include Link Explorer (backlink research), Keyword Explorer (keyword research with volume and difficulty), Rank Tracker, Site Crawl (technical audits), and On-Page Optimizer. Moz's proprietary metrics include Domain Authority (DA), Page Authority (PA), and Spam Score. The Link Index is smaller than Ahrefs' but Moz's metrics — particularly DA — are widely referenced in the SEO industry as shorthand for domain strength.
Quick example
A link building agency receives a placement offer on a site with DA 65. They check the domain in Moz Link Explorer, review the Spam Score (ideally below 8%), and look at the site's top linking domains. DA and Spam Score together give a quick quality assessment — though neither is used by Google, they are widely understood industry benchmarks.
Quick facts
| Meaning | An SEO platform known for Domain Authority and link research tools |
|---|---|
| Main category | SEO tools and link research |
| Used by | SEO agencies, in-house teams, content marketers, link builders |
| Difficulty | Intermediate |
| Importance | High |
| Common examples | Domain Authority checks, link research, keyword research, rank tracking, site audits |
| Still relevant? | Yes. Moz Pro remains a capable SEO platform, and Domain Authority is the most widely cited authority metric in the industry. However, Ahrefs and Semrush have larger databases and more features. Moz is most valuable for its metrics and educational content. |
Why Moz matters
Moz matters for two reasons: Domain Authority has become the industry-standard shorthand for domain strength, and Moz Pro remains a competent all-in-one SEO platform. Even teams that use Ahrefs or Semrush as their primary tool often reference DA because clients and publishers understand it.
Domain Authority is the most widely cited authority metric
When a publisher offers a guest post on a "DA 60 site" or a client asks for links from "DA 40+ domains," they are referencing Moz's metric. DA has become a shared vocabulary across the SEO industry, even among people who do not use Moz Pro directly.
Spam Score helps identify low-quality sites
Moz's Spam Score (0-100%) flags sites that exhibit patterns common to spam sites — thin content, suspicious link patterns, and duplicate content. It is a useful screening tool when evaluating link placement opportunities.
Link Explorer provides a second link index
No single crawler sees every link. Comparing backlink data from Moz and Ahrefs gives a more complete picture of a domain's link profile. Where the two agree, confidence is higher; where they differ, it is worth investigating why.
Keyword Explorer includes a unique difficulty-to-opportunity analysis
Moz's Keyword Difficulty score is supplemented by a "Priority" score that combines difficulty, volume, and opportunity — helping prioritise which keywords to target first. The SERP analysis also shows which SERP features are present.
Moz Academy and educational content set it apart
Moz invests heavily in SEO education — the Moz Blog, Whiteboard Friday, and Moz Academy. For teams building SEO knowledge, this content is a genuine differentiator that other platforms do not match.
How it works
Moz operates a web crawler (Rogerbot) that builds its Link Index, and exposes that data through a suite of tools.
- 1
Rogerbot crawls the web
Moz's crawler, Rogerbot, discovers pages and records the links it finds. The resulting Link Index is smaller than Ahrefs' but is regularly refreshed. Links are stored with attributes including anchor text, link type, and first/last seen dates.
- 2
Domain Authority is calculated from the link graph
DA is a 0-100 logarithmic score that predicts how likely a domain is to rank in search results. It is calculated from the quantity and quality of linking root domains. Moving from DA 20 to 30 is much easier than moving from DA 70 to 80.
- 3
Spam Score is calculated from spam signals
Spam Score is based on 27 spam flags — patterns correlated with penalised or low-quality sites. A score of 1-30% is low risk, 31-60% is moderate, and 61-100% is high. It is a screening tool, not a definitive quality judgement.
- 4
Keyword data is aggregated from multiple sources
Keyword Explorer combines data from Google Keyword Planner, clickstream data, and Moz's own SERP analysis. Volume estimates, difficulty scores, and SERP features are presented together with a Priority score for prioritisation.
- 5
Tools expose the data through focused interfaces
Link Explorer, Keyword Explorer, Rank Tracker, and Site Crawl each present filtered views of the underlying data, designed for specific SEO workflows.
Types and variations
Moz is described by its main tools and metrics.
Link Explorer
The core link research tool. Shows backlinks, referring domains, anchor text, and link type for any domain. Includes inbound link comparison between domains and new/lost link tracking.
Domain Authority (DA)
A 0-100 logarithmic score predicting a domain's ability to rank. The most widely cited authority metric in the SEO industry, though not used by Google. DA is relative — compare domains against each other, not against an absolute standard.
Page Authority (PA)
The page-level equivalent of DA. Predicts the ranking strength of a single URL rather than a whole domain. Less commonly cited than DA but useful for evaluating specific linking pages.
Spam Score
A 0-100% score based on 27 spam signals. Helps identify sites that may be penalised or low quality. A high Spam Score does not prove a site is spam — it flags patterns that warrant further investigation.
Keyword Explorer
Keyword research with volume, difficulty, opportunity, and priority scores. Includes SERP analysis and keyword suggestions. Smaller keyword database than Semrush or Ahrefs.
Rank Tracker
Tracks keyword positions across search engines and locations. Includes weekly tracking, SERP feature monitoring, and competitor comparison.
Site Crawl
A cloud-based site auditor that checks for technical SEO issues including crawlability, redirects, metadata, and structured data. Less configurable than Screaming Frog but convenient for ongoing monitoring.
MozBar
A free browser extension that shows DA, PA, and Spam Score for any page you visit, directly in the SERP or on the page. Useful for quick checks without opening the full Moz interface.
Real examples
How Moz gets used in practice.
Evaluating a link placement offer
A publisher offers a guest post on a DA 55 site. You check the domain in Link Explorer: DA 55 confirmed, Spam Score 4%, 1,200 referring domains, top links come from genuine publications. The placement looks legitimate. Without this check, a "DA 55" claim is just a number — it could be inflated by spammy links.
Quick SERP analysis with MozBar
Install the free MozBar extension, search for your target keyword, and see DA and PA for every result on the SERP. If the top 10 results are all DA 70+ and your site is DA 25, you know instantly that ranking for this keyword will require significant link building work.
Comparing DA directly with DR
A client asks for "DR 50 or DA 50 links" as though the two are equivalent. They are not — Moz and Ahrefs use different indexes and different formulas. A DA 50 site might be DR 45 or DR 58. Pick one metric for your campaign and use it consistently.
Treating DA as a Google ranking factor
Telling a client that raising their DA from 30 to 40 will improve rankings. DA is Moz's proprietary metric — Google does not see or use it. Rankings are influenced by Google's own signals, not by a third-party score. DA is useful for relative comparison, not as a ranking input.
Best practices
Moz is most valuable for its metrics and link research. Use it alongside other tools for a complete picture.
What to do
- Use DA as a relative comparison metric between domains, not as an absolute quality measure
- Always check Spam Score alongside DA when evaluating link opportunities
- Use MozBar for quick SERP analysis — it is free and saves opening a full tool
- Cross-reference Moz link data with Ahrefs for important link building decisions
- Use Keyword Explorer's Priority score to rank keyword opportunities by effort vs reward
- Take advantage of Moz's educational content — the blog and Whiteboard Friday are genuinely useful
What to avoid
- Treating DA as a Google ranking factor — it is not
- Comparing DA with Ahrefs DR or Semrush Authority Score as though they are equivalent
- Using Moz as your only link research tool — its index is smaller than Ahrefs
- Ignoring Spam Score when evaluating link opportunities — a high DA with high Spam Score is a red flag
- Reporting DA changes to clients as though they directly cause ranking changes
Common mistakes
Confusing Domain Authority with Google's signals
DA is Moz's proprietary metric, calculated from Moz's link index. Google has its own link signals and does not use DA. A site can have high DA and poor rankings, or low DA and strong rankings. DA is a comparative tool, not a ranking input.
Comparing DA across tools
DA (Moz), DR (Ahrefs), and Authority Score (Semrush) all measure domain strength but use different indexes and formulas. A DA 50 is not equivalent to a DR 50. Pick one metric for internal consistency and do not mix scores from different providers.
Overreacting to DA fluctuations
DA can change when Moz updates its index or its algorithm, not because your site's actual link profile changed. A sudden DA drop may be a recalibration, not a problem. Always check whether Moz announced an index update before panicking.
Ignoring the Link Index size difference
Moz's Link Index is smaller than Ahrefs'. For comprehensive backlink research — especially competitor analysis and prospecting — Ahrefs will show more referring domains. Use Moz for DA and Spam Score checks, but use Ahrefs for the actual link research.
Not using the free MozBar extension
MozBar is free and shows DA, PA, and Spam Score directly in search results. It is one of the most useful free SEO tools available, and many paid Moz users do not realise it is available to everyone.
Dismissing Moz because of database size
While Moz's link database is smaller, its metrics (DA, Spam Score) and educational content are genuinely valuable. Dismissing Moz entirely because Ahrefs has more links misses the point — they serve different purposes in an SEO workflow.
Moz's evolving position in the SEO tool market
Moz was once the dominant SEO tool, but Ahrefs and Semrush have grown larger databases and broader feature sets. Moz's response has been to focus on what it does uniquely well: Domain Authority as an industry-standard metric, Spam Score as a quality screening tool, and SEO education through the Moz Blog and Whiteboard Friday. For many teams, Moz is now a secondary tool — used for DA checks and Spam Score rather than as the primary research platform. But DA's position as the most widely cited authority metric means Moz remains relevant even to people who do not subscribe to Moz Pro.
- Domain Authority remains the most widely referenced authority metric in the SEO industry
- Moz's link index is smaller than Ahrefs — supplement for comprehensive link research
- MozBar is one of the best free SEO tools available and is underused even by paid subscribers
- Moz's educational content is a genuine differentiator that no other platform matches
How iNet Ventures approaches moz
We reference Domain Authority in client communications because it is the metric clients and publishers understand. Internally, we use Ahrefs DR for link research and qualification, but we report DA alongside DR because clients expect it. We use Spam Score as a screening tool when evaluating link placement opportunities.
Link qualification
When evaluating a link placement opportunity, we check DA, Spam Score, and referring domains in Moz, alongside DR and organic traffic in Ahrefs. Both tools together give a more complete picture than either alone.
Client reporting
We include DA in client reports because it is the metric clients recognise. We pair it with referring domains and organic traffic data to provide context — a DA number alone is meaningless without those.
Prospect screening
We use MozBar for quick checks during prospecting — a DA and Spam Score in the browser saves opening a full tool for every site we visit.
Continue learning
Best SEO Link Building Tools
How Moz compares against Ahrefs and Semrush.
Domain Authority Checker
Look up DA for any domain instantly.
Free Backlink Analyzer
Check a backlink profile without a paid subscription.
Link Building Plans
Monthly link building with no contracts.
Competitor Link Building
We turn competitor research into live link placements.
Frequently asked questions
What is Domain Authority?
Domain Authority (DA) is Moz's 0-100 logarithmic score that predicts how likely a domain is to rank in search results. It is calculated from the quantity and quality of linking root domains. DA is not used by Google — it is a comparative tool for evaluating domains against each other. A DA 50 site is stronger than a DA 30 site, but DA does not cause rankings.
How does Moz compare to Ahrefs and Semrush?
Moz has a smaller link index than Ahrefs and a smaller keyword database than Semrush. However, Moz's Domain Authority is the most widely cited authority metric in the industry, and Spam Score is a useful quality screening tool. Many teams use Moz for metrics and Ahrefs or Semrush for deep research.
Is there a free version of Moz?
Moz offers a free community account with limited Link Explorer queries (10 per month), a free Keyword Explorer with limited searches, and the free MozBar browser extension. The MozBar is genuinely useful — it shows DA, PA, and Spam Score for any page directly in search results at no cost.
What is Moz Spam Score?
Spam Score is a 0-100% metric based on 27 spam signals — patterns correlated with penalised or low-quality sites. A score of 1-30% is low risk, 31-60% is moderate, and 61-100% is high. It is a screening tool, not a definitive judgement. A high Spam Score warrants further investigation but does not prove a site is spam.
Does Google use Domain Authority?
No. DA is Moz's proprietary metric, calculated from Moz's link index. Google has its own link signals and ranking algorithms and does not reference DA or any third-party authority score. DA is useful for relative comparison between domains, not as a ranking input.
Why does my DA keep changing?
DA can fluctuate when Moz updates its Link Index or recalibrates its algorithm, not necessarily because your backlink profile changed. Check the Moz blog for index update announcements before interpreting a DA change as a real change in your site's authority.
Written from hands-on use of Moz Pro and MozBar alongside Ahrefs and Semrush. Metric definitions are checked against Moz's own documentation, and we clearly distinguish between Moz's proprietary metrics and Google's actual ranking signals.
- Written by:
- iNet Ventures Editorial Team
- Reviewed by:
- iNet Ventures Link Building Team
- Published:
- 18 August 2026
- Last reviewed:
- 18 August 2026
Sources and further reading
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