If you’ve spent any time reading about SEO, you’ve bumped into the term “domain authority” — usually with people fretting over the number like it’s a school report card. So what is domain authority, really? It’s a handy gauge of how strong your website looks to search engines, but it’s also one of the most misunderstood metrics in the business. In this guide we’ll explain what domain authority is, what it definitely isn’t, how it’s worked out, how to check yours, and the sensible way to improve it — in plain English, no jargon required.
Domain authority (DA) is a score from 1 to 100, created by the SEO company Moz, that predicts how likely a website is to rank in search results. A higher score suggests stronger ranking potential. Crucially, it’s a third-party metric — Google does not use domain authority as a ranking factor. Treat it as a comparison tool, not a target.
What is domain authority?
Domain authority is a predictive score developed by Moz that estimates how well an entire website might perform in organic search. It runs on a scale from 1 to 100, and the calculation leans heavily on your backlink profile — how many other websites link to you, and how trustworthy those linking sites are. The idea is simple: if lots of respected websites vouch for you with links, you probably deserve to rank well, so your score climbs.
The most important thing to understand is that domain authority is an estimate, not an official figure. Moz built it to give marketers a quick, single number to compare websites at a glance, in the same way a credit score gives lenders a fast read on borrowers. It’s genuinely useful for that. But it’s a model’s best guess, not a peek inside Google’s algorithm.
Is domain authority a Google ranking factor?
No — and this is the myth worth burning to the ground. Google has repeatedly confirmed it does not use Moz’s domain authority, or any single “authority score”, to rank pages. Google’s systems weigh hundreds of signals, including relevance, content quality, page experience, links and a range of off-page SEO signals. There is no field in Google’s ranking system labelled “DA”.
So why does anyone care? Because the things that push your domain authority up — quality backlinks, helpful content, a healthy site — are the same things that genuinely help you rank. DA is the thermometer, not the temperature. Watching the thermometer is fine; just don’t confuse it with the weather. If you want to climb the results pages, focus on the underlying work covered in our guide to how to rank higher on Google.
How is domain authority calculated?
Domain authority is built largely on links. Moz crawls a huge index of the web and looks at signals such as the number of unique websites linking to you (your linking root domains), the quality and relevance of those sites, and how your overall link profile compares to everyone else’s. It then runs this through a machine-learning model that’s trained to mirror Google’s actual search results as closely as possible.
A few practical points follow from that:
- Quality beats quantity. A handful of links from trusted, relevant websites move the needle far more than hundreds of links from low-quality directories or spammy blogs.
- It’s recalculated regularly. Moz refreshes its index and re-scores sites periodically, so your number can shift even if you’ve done nothing — usually because competitors changed or the index updated.
- It’s relative. Because the model is calibrated against the whole web, your score depends partly on what everyone else is doing, not just your own effort.
If you want the technical detail straight from the source, Moz documents exactly how it builds domain authority.
Domain authority vs Ahrefs DR vs Semrush Authority Score
Moz isn’t the only company with an authority metric. The two other big SEO tools have their own versions, and they don’t agree with each other — which is exactly why you should never compare a Moz score to an Ahrefs score and panic. Each tool uses its own web crawl and its own formula, so the same website can score quite differently across all three.
| Metric | Tool | Scale | Mainly based on |
|---|---|---|---|
| Domain Authority (DA) | Moz | 1–100 | Link profile, modelled to predict ranking ability |
| Domain Rating (DR) | Ahrefs | 0–100 | Strength of the backlink profile (linking domains) |
| Authority Score (AS) | Semrush | 0–100 | Links, organic traffic and natural-traffic signals |
Ahrefs explains its own approach to Domain Rating in detail. The takeaway: pick one tool, track that one number over time, and compare yourself only to competitors measured by the same tool. Mixing metrics is how people end up confused and demoralised for no reason.
What’s a good domain authority score?
There’s no universal “good” number — it’s entirely relative to your competition. A brand-new website starts near 1. Scores in the 20s and 30s are perfectly solid for a growing small business; 40 and above is strong; and the biggest global brands sit up in the 90s. A local plumber competing with other local plumbers needs a very different score from a national retailer fighting household names.
The other thing to know is that the scale is logarithmic. That’s a fancy way of saying the gaps get harder as you climb. Moving from 20 to 30 is achievable with steady effort; moving from 70 to 80 is a serious, long-term undertaking. So if your score has stalled at a higher level, that’s normal, not failure. The smart move is to open up a tool, check the domain authority of the sites already ranking for your target keywords, and aim to match or beat them — not some arbitrary figure you read online.
How to check your domain authority
Checking domain authority takes about thirty seconds, and you don’t need to pay for anything to get started:
- Use a free checker. Moz’s free Link Explorer and its MozBar browser extension will show your DA. Free plans cap how many checks you get per month, which is fine for occasional use.
- Try the alternatives. Ahrefs has a free Website Authority Checker, and Semrush offers limited free lookups too. Run a couple so you understand how the numbers differ.
- Check competitors at the same time. The score only means something in context, so look up three or four rivals while you’re there and note where you sit.
- Record it and track the trend. Jot down the figure with the date. The direction of travel over months matters far more than today’s exact number.
One reminder: stick to a single tool for your own tracking. If you measured DA last quarter, measure DA this quarter — don’t switch to DR and convince yourself something dramatic happened.
How to improve your domain authority
You can’t edit your domain authority directly — it’s a reflection of the real work you do. Improve the fundamentals and the number follows. Here’s where to put your energy, roughly in order of impact:
- Earn quality backlinks. Links from relevant, trusted websites are the single biggest driver. A few great links beat a hundred weak ones every time. This is the heart of off-page SEO, and it’s worth doing properly rather than chasing shortcuts.
- Publish genuinely helpful content. Useful guides, original data, tools and answers are what people actually link to and share. Great content is a link magnet — it does the heavy lifting for you over time.
- Fix your technical SEO. A fast, crawlable, mobile-friendly, secure site helps every other effort land. If search engines can’t crawl you or your pages are slow, all that good content and those links are working uphill.
- Build smart internal links. Linking your own pages together spreads authority around your site and helps search engines understand what matters. It’s free, fully in your control, and often neglected.
- Give it time and stay consistent. Authority compounds. Buying links or using dodgy schemes can crash your rankings and aren’t worth the risk. Steady, white-hat work wins.
Notice that none of these are “domain authority hacks”. They’re just good SEO. Do them, and your domain authority rises as a side effect — which is exactly how it should be. Wondering whether links are still worth the effort in an AI-driven search world? We answer that in do backlinks still matter?
Domain authority myths and mistakes to avoid
Plenty of SEO grief comes from misunderstanding this one metric. Here are the traps we see most often:
- “Google uses my DA.” It doesn’t. Repeat as needed.
- Comparing scores across different tools. A Moz DA of 30 and an Ahrefs DR of 45 aren’t contradictory — they’re different rulers measuring the same thing.
- Obsessing over the exact number. A one- or two-point wobble is noise from an index refresh, not a crisis or a triumph.
- Buying links to inflate it. This can temporarily nudge a third-party score while quietly tanking your actual Google rankings. Bad trade.
- Ignoring relevance. A link from a wildly unrelated site is worth far less than one from a site in your industry, whatever it does to the headline figure.
- Treating DA as the goal. Rankings, traffic, leads and sales are the goal. Domain authority is just a rough progress indicator along the way.
Frequently asked questions
What is domain authority in simple terms?
What is domain authority? It’s a 1–100 score from Moz that predicts how likely your website is to rank in search results, based mainly on the strength of your backlink profile. Think of it as a quick, comparative health check for your site’s authority — useful, but not an official Google number.
Does Google use domain authority?
No. Domain authority is a third-party metric from Moz. Google has stated it doesn’t use it as a ranking factor. However, the things that raise your DA — quality links and helpful content — genuinely do help you rank, which is why it’s still a worthwhile gauge.
How do I increase my domain authority?
Earn quality backlinks from relevant, trusted websites, publish link-worthy content, fix technical issues, build internal links, and give it time. There’s no instant fix or legitimate shortcut — anyone selling one is selling you risk.
What is a good domain authority score for a small business?
Anything in the 20s to 30s is healthy for a growing small business, and 40-plus is strong. But what truly matters is how you compare to your direct competitors for the keywords you actually want to rank for.
Why did my domain authority drop without me doing anything?
Usually it’s because Moz refreshed its index or your competitors gained ground — the score is relative and recalculated periodically. Small movements are normal. Only a sustained downward trend is worth investigating.
Is a higher domain authority always better?
A higher score generally signals stronger ranking potential, but it’s not the prize itself. A site with a modest DA and brilliant, relevant content can outrank a higher-DA site on specific searches. Chase rankings, traffic and leads — let DA tag along.
Free resource: work through our free 50-point SEO audit checklist to see exactly what to fix on your site – no email required.
Want to build real authority?
You don’t need to obsess over a number — you need a site that earns trust the right way. We help small businesses across the UK and USA grow with quality content and genuine white-hat link building, from £79/month (about $99). Get a free SEO audit to see exactly where you stand, or explore our services & pricing to find the plan that fits.