Links API Help – Help Hub – Moz

What Is the Moz Links API?

The Moz Links API is a programmatic interface for accessing information collected through Moz’s link index. It can return authority scores, backlink counts, referring-domain information, anchor text, link status, top pages, redirect destinations, and other data associated with domains and individual URLs.

It is important to understand what the service does not do. It does not create backlinks, submit links to search engines, guarantee rankings, or magically persuade authoritative publications to mention your company. It supplies data that can support research, reporting, prospecting, auditing, and competitive analysis.

Common applications include:

• Adding Domain Authority and Page Authority to an internal dashboard
• Evaluating domains during digital PR or outreach research
• Monitoring changes in referring domains
• Finding competitor pages that attract strong backlinks
• Comparing the backlink profiles of multiple websites
• Enriching a CRM with domain-level SEO metrics
• Screening large domain lists before a manual quality review

The current API generally uses version 2 endpoints with JSON request and response bodies. A typical URL Metrics request is sent as an HTTP POST request and authenticated with an Access ID and Secret Key through HTTP Basic Authentication. Legacy version 1 documentation may describe signed URLs, expiration timestamps, HMAC signatures, and numerical bit flags, so developers should not mix examples from the two versions.

Understanding the Most Important Moz Link Metrics

Domain Authority

Domain Authority, commonly abbreviated as DA, is a comparative Moz score intended to estimate the ranking potential of a root domain. It is usually presented on a 1-to-100 scale. A higher score indicates stronger estimated authority within Moz’s model, but DA is not a metric used directly by Google or Bing.

DA is most useful when comparing similar websites. Comparing a local plumbing company with Wikipedia provides approximately the same strategic insight as comparing a bicycle with an aircraft carrier. Compare direct competitors, comparable publishers, or domains operating in the same market.

Page Authority

Page Authority, or PA, estimates the ranking potential of a specific page rather than an entire root domain. A strong domain can contain low-authority pages, while an especially successful article or resource can earn a higher PA than other pages on the same website.

PA is helpful when reviewing competitor content, examining potential outreach targets, or identifying which pages on your own site have accumulated the strongest link equity.

Spam Score

Spam Score is a risk-oriented indicator based on patterns Moz has observed across websites. It should be treated as a screening signal, not an automatic verdict. A relatively high score does not prove that a site is malicious, penalized, or harmful. It means the domain deserves closer inspection.

Before rejecting a domain, manually check its content quality, ownership, traffic patterns, outbound-link behavior, topical relevance, index status, and the context surrounding the actual backlink.

Linking Root Domains

This metric counts unique root domains linking to a target. Ten links from ten independent websites can indicate broader endorsement than ten thousand template links from one domain. That does not make every unique domain valuable, but it explains why referring-domain diversity is frequently more informative than raw backlink volume.

External Links, Nofollow Links, and Redirect Links

The API can expose different categories of inbound links, including external links, links associated with redirects, and links carrying nofollow-related attributes. These distinctions help analysts understand how a backlink profile was assembled instead of staring at one giant total and hoping it reveals its secrets.

Link Propensity and Supporting Fields

Depending on the endpoint and subscription access, responses may include fields such as HTTP status, page title, last crawl date, root domain, subdomain, deleted-link counts, outbound-domain counts, and link propensity. Moz documentation describes link propensity as an estimate of how likely a domain is to link to other root domains.

Major Moz Links API Endpoints

You do not need every endpoint for every project. Selecting the narrowest endpoint that answers the business question keeps responses simpler and makes quota planning easier.

URL Metrics

The URL Metrics endpoint is the usual starting point. It accepts one or more targets and returns metrics associated with those URLs or domains. Typical output can include DA, PA, Spam Score, HTTP status, referring-domain counts, and link totals.

Use it for bulk domain qualification, recurring authority reports, CRM enrichment, domain comparisons, and lightweight SEO applications.

Links

The Links endpoint returns individual links associated with a target. This is useful when you need the actual linking pages rather than only aggregate totals. Depending on the query options, you may inspect source pages, target pages, anchor text, link attributes, and authority-related information.

Linking Root Domains

This endpoint focuses on the unique domains linking to a target. It is valuable for competitor research, partnership discovery, outreach prospecting, and measuring referring-domain growth.

Anchor Text

The Anchor Text endpoint helps reveal the words and phrases used in links pointing to a page or domain. A natural profile often includes brand names, URLs, descriptive phrases, generic language, image links, and miscellaneous wording. An unusually repetitive commercial pattern may deserve investigation.

Link Intersect

Link Intersect identifies domains or pages that link to selected competitors but do not link to your target. For link builders, this endpoint can turn a vague instruction such as “find more opportunities” into a prioritized list of publications, associations, directories, partners, and resource pages.

Top Pages

The Top Pages endpoint identifies pages with strong link-based metrics. Use it to discover which competitor resources attract citations, which content formats earn attention, and which pages on your own site deserve updating, redirecting, or further promotion.

Link Status and Final Redirect

Link Status can help determine whether a link relationship exists, while Final Redirect resolves where a URL ultimately leads. Redirect resolution is particularly useful during website migrations, expired-domain research, broken-link reclamation, and historical backlink audits.

Index Metadata and Usage Data

Index Metadata provides context about the underlying link index. Usage Data helps teams monitor API consumption. Production applications should check usage proactively instead of discovering a depleted allowance when a client report contains seventeen blank columns and one very nervous account manager.

How to Authenticate a Moz Links API Request

For a version 2 request, the Access ID is generally used as the Basic Authentication username and the Secret Key as the password. Credentials should be stored in environment variables or a managed secret vault.

Never expose the Secret Key in browser-side JavaScript, public repositories, mobile application code, shared spreadsheets, analytics events, or URLs. Calls should be made through a trusted server-side application.

Example cURL Request

The service returns JSON results corresponding to the requested targets. Exact response fields can vary by endpoint, request options, account level, and API changes, so applications should tolerate missing or null values.

Example PHP Integration

Scopes, URL Normalization, and Why Results Sometimes Look Wrong

Many confusing API results are caused by inconsistent targets rather than broken data. These URLs may represent related but distinct resources:

• http://example.com
• https://example.com
• https://www.example.com
• https://example.com/
• https://blog.example.com
• https://example.com/category/page

Create a normalization policy before collecting data. Resolve canonical hosts, standardize protocols, remove tracking parameters, preserve meaningful paths, and record redirects. Otherwise, a monthly report may compare one URL variant with another and announce a dramatic SEO change that is actually punctuation wearing a fake mustache.

Also decide whether the question concerns an exact page, a subdomain, or a root domain. Page-level PA should not be compared as though it represents the authority of the entire website.

Pagination, Row Limits, and Efficient API Usage

Moz API plans may measure consumption in returned data rows rather than treating every HTTP request as equal. A request that returns hundreds of link records can therefore consume more allowance than a compact metrics request. Monthly row allowances and concurrency limits vary by subscription.

Endpoints that return long lists may provide a continuation token, commonly represented as a next token. Store that value and submit it with the following request instead of guessing numeric page offsets.

Practical Efficiency Rules

• Request only the data required for the current workflow.
• Use batch requests where supported to reduce connection overhead.
• Cache slow-changing authority metrics for an appropriate period.
• Do not recalculate an entire domain inventory because one record changed.
• Deduplicate normalized targets before sending them.
• Record rows consumed by endpoint, project, and customer.
• Schedule bulk jobs away from interactive application traffic.
• Stop pagination when the continuation token disappears.

A daily dashboard may not need fresh DA and PA values every five minutes. Caching those values for a day or longer can lower costs without reducing practical usefulness.

Troubleshooting Common Moz Links API Errors

HTTP 400: Invalid Request

Review the JSON payload, target format, endpoint path, supported filters, sort options, and required properties. Log the final serialized request body, but redact credentials.

HTTP 401 or 403: Authentication or Access Problem

Confirm that the Access ID and Secret Key are correct, active, and attached to the expected account. Check whether the selected endpoint or metric is available on the subscription plan.

HTTP 429: Limit Reached

The application may be sending requests too quickly, exceeding concurrency limits, or exhausting its allowance. Use a queue, limit parallel workers, monitor usage, and retry only when appropriate.

HTTP 500-Level Errors

Temporary server failures should be retried with capped exponential backoff and random jitter. Do not retry indefinitely. After several failures, move the job to a retry queue and raise an alert.

Empty or Missing Results

The target may be new, lightly linked, blocked, malformed, redirected, or absent from the current link index. A null value is not necessarily zero, and zero is not necessarily an error. Preserve that distinction in your database.

Different Numbers Across SEO Tools

Moz, Google, Bing, and other platforms operate separate crawlers, indexes, processing rules, and update schedules. Their totals should not be expected to match exactly. Google states that links help it discover pages and can act as relevancy signals, while Bing Webmaster APIs can expose link details for verified properties. Those first-party tools and Moz’s independent index answer related but different questions.

How to Use Moz Link Data Without Making Bad SEO Decisions

Authority metrics are useful filters, not substitutes for judgment. A backlink opportunity should also be evaluated for topical relevance, editorial quality, real readership, placement context, traffic potential, and brand safety.

A modestly authoritative industry association may be more valuable than a high-DA general directory containing thousands of unrelated outbound links. Likewise, one editorial mention that sends qualified customers can outperform hundreds of links created solely to inflate a report.

Google’s current guidance emphasizes crawlable links, understandable anchor text, people-first content, and compliance with spam policies. Paid placements should be qualified appropriately, while user-generated and nofollow links may require relevant rel values. API data should help identify patterns and opportunities, not encourage manipulative link schemes.

Useful Moz Links API Workflows

Competitor Link Gap Analysis

1. Select three to five true search competitors.
2. Run Link Intersect or collect their linking domains.
3. Remove domains already linking to your site.
4. Enrich the remaining domains with DA, Spam Score, and relevance labels.
5. Inspect the actual linking pages.
6. Group opportunities by tactic, such as research citations, resource pages, directories, podcasts, or partnerships.

Content Performance Analysis

Retrieve competitor top pages, classify each page by format and topic, and compare referring domains. This can reveal whether the market rewards original research, free tools, templates, statistics pages, tutorials, or controversial articles about whether pineapple belongs on pizza.

Backlink Monitoring

Store periodic snapshots of referring-domain and link counts. Compare snapshots to identify meaningful gains or losses, then investigate the source records. Avoid alarming stakeholders over tiny fluctuations that fall within normal crawler and index variation.

Prospect Qualification

Enrich an outreach list with Moz metrics, but apply topical and editorial checks before contacting anyone. Automated filtering should reduce manual work, not automate bad taste at industrial scale.

Experiences From Building With the Moz Links API

The first lesson from a real integration is that obtaining a successful response is the easy part. A developer can often send the first URL Metrics request within an hour. The difficult work begins when the API must support thousands of domains, multiple customers, scheduled reports, retries, changing URLs, and budget limits.

One of the most useful early decisions is to create a canonical target table. Each submitted URL receives a normalized URL, root domain, subdomain, original input, redirect destination, and last-checked timestamp. Without that table, duplicate records multiply quickly. Marketing uploads example.com, sales uploads www.example.com, and an analyst uploads the HTTPS homepage. The system treats them as three exciting new discoveries until someone notices that all three have the same logo.

A second lesson is to store raw responses alongside parsed metrics. Parsed columns are convenient for dashboards, but raw JSON becomes invaluable when Moz adds fields, a parser contains a bug, or a customer asks why last month’s result changed. Raw responses provide an audit trail and allow old records to be reprocessed without repurchasing the same data.

Quota awareness also needs to be designed into the application from the beginning. A prototype may call the API whenever a user refreshes a page. That feels responsive until several customers refresh at once and a month’s allowance begins evaporating like water on a Phoenix sidewalk. A production system should usually return cached results immediately, mark stale records for refresh, and process those refreshes through a controlled queue.

The best dashboards avoid presenting DA as a pass-or-fail grade. In practice, users become overly attached to a single number. They celebrate a one-point increase as though the company has won a major award and treat a one-point decline as a corporate emergency. Better reporting combines authority metrics with referring-domain growth, newly discovered links, lost links, relevance, organic visibility, conversions, and actual referral traffic.

Another practical issue is partial data. Some URLs will return missing fields, stale crawl dates, redirects, or no known links. Code that assumes every property exists eventually crashes during the most important report of the month. Defensive parsing is not glamorous, but neither is explaining to a client that the dashboard broke because one obscure PDF had no Page Authority value.

Comparisons across providers require restraint. Different backlink tools regularly disagree because they crawl different portions of the web. The productive question is not, “Which total is the one sacred number?” It is, “Is this source internally consistent enough to measure trends and support decisions?” For recurring reports, consistency of method is usually more valuable than chasing identical totals across unrelated indexes.

Finally, the strongest implementations keep machines and humans in their proper roles. The API is excellent at sorting ten thousand domains by authority, identifying repeated anchor text, and finding unusual changes. A human is still better at deciding whether a publication is respected, whether a link is contextually relevant, and whether contacting the editor would build a relationship or merely produce another email beginning with “Dear website owner.”

The Moz Links API delivers the most value when it becomes part of a broader decision system: normalize the targets, collect the right endpoint data, cache intelligently, monitor usage, flag anomalies, and reserve manual attention for the opportunities that genuinely matter.

Conclusion

The Moz Links API provides a practical way to bring backlink intelligence and authority metrics into custom software. URL Metrics is the easiest entry point, while endpoints for links, referring domains, anchor text, intersections, redirects, and top pages support deeper SEO research.

A reliable integration requires more than copying an API example. Protect the credentials, normalize URLs, understand scope, cache suitable results, monitor row consumption, paginate correctly, and expect incomplete data. Most importantly, interpret Moz metrics as comparative indicators rather than direct search-engine scores.

Used carefully, the API can save hours of manual research and make competitive analysis more repeatable. Used carelessly, it can produce an expensive database filled with duplicate URLs and impressive-looking numbers that nobody knows how to act upon. The difference is not the endpoint. It is the workflow built around it.