Domain Authority is the SEO industry's most cited authority metric. This free DA checker returns a 0-100 score for any domain in about two seconds, with no ads, no popups and no signup — and every check comes with an embeddable DA badge for your own site. When Moz's free API has quota left we serve its official score; when it doesn't, we serve a transparent estimate derived from the open OpenPageRank dataset and label it as an estimate on screen. You always know which number you are looking at.
Domain Authority is a 0-100 search-engine ranking score developed by Moz. It predicts how well a website will rank on Google's search results pages, calculated from the quality and quantity of inbound backlinks. Higher DA = better SEO authority. A DA above 50 is excellent for most niches.
Three reliable levers: (1) earn high-quality backlinks from authoritative sites in your niche, (2) publish in-depth long-form content that other sites want to cite, (3) prune low-quality / spammy backlinks via Google's Disavow Tool. DA updates monthly — patience compounds.
We read Moz's official API while its free quota lasts and cache every answer aggressively, so you get Domain Authority + Page Authority + Spam Score without paying for a Moz Pro subscription. Past that quota the score switches to an OpenPageRank-derived estimate, clearly labelled, instead of an error page. Plus a free, customizable DA badge widget — exactly the kind of trust signal advertisers and link-buyers want to see on your site.
They are not rivals, they are two vendors’ guesses at the same thing. DA is Moz’s prediction of how likely a domain is to rank; DR is Ahrefs’ measure of how strong its backlink profile is. Neither is a Google ranking factor, and no Google engineer has ever said otherwise. What matters is the gap between them: a high DR with a low DA usually means a newer site that earned a few big links but has no ranking history yet, while a high DA with a low DR is the signature of an established domain whose link profile has gone quiet. Pick one, check it monthly, and write the number down — a score with six months behind it is a diagnosis, while a score checked twice in a week is noise.
Most free DA tools will not tell you this, so here it is plainly. Moz gives away a small monthly API allowance. While it lasts, this checker returns Moz’s official Domain Authority, Page Authority and Spam Score, cached so repeat lookups cost nothing. Once that allowance is spent — and on a free tool serving thousands of lookups it does get spent — there are two options: show you an error, or show you a transparent substitute. We chose the substitute: a 0-100 figure derived from the open OpenPageRank dataset, rescaled to the familiar DA range and labelled ‘estimated’ on screen, so you are never guessing which number you are holding. Treat an estimate as directionally useful for comparing and tracking domains, not as a figure to quote back at Moz.
Copy the HTML snippet below and paste it anywhere on your site — header, sidebar, footer, About page. The badge auto-refreshes weekly. Works on WordPress, Shopify, Wix, Webflow, Ghost CMS, Squarespace, Blogger, and plain static HTML.