Free Backlink Checker
Type a domain. We tell you which websites link to it — up to a hundred of them, ranked by how much that link is actually worth — not just how many. Computed on our own machine from the public Common Crawl web graph. No account, no card, no daily limit, and you can take the list away as a CSV.
We ship data for every domain with at least 20 qualified referring domains. If a name is not in that slice, it has fewer than 20 — that is the answer, not a missing result.
How it works
Type a domain
Just the name —
example.com. No http, no www, no sign-up, and no counter ticking down in the corner. Check yours, check a competitor, check one you are thinking of buying.Read who links to it
You get the qualified referring-domain count, an authority score from 0 to 100, and the list itself — ordered so the links that mean something come first.
Take it with you
Download the list as CSV, or call the same numbers from the free API below. No key, no quota, and nothing to cancel.
What a referring domain is, and why it is the number that counts
Backlinks is the vanity number. A thousand links from one forum is still one website that likes you. The number that survives contact with reality is how many distinct domains link to you — the referring-domain count — and it is the number every paid tool sells you by the month.
We did not buy it. The Common Crawl web graph is public: 2,450,405,793 links between 119,722,885 domains. We pulled the whole thing onto one machine and counted it ourselves. What you are querying is that count, plus the list behind it.
The ordering is the part we had to fix
The first version of this page ranked referring domains by authority alone.
It looked excellent and it was useless: the top of the list was
google.com, apple.com, wikipedia.org, cloudflare.com — for every
domain we tried. A list whose head is identical for the whole web tells you
nothing about your site.
The missing piece was not a filter. It was a denominator. A domain that links to six million other domains is not endorsing you by linking to you; it is linking to everything. So the ordering divides:
value = authority ÷ log10(outbound domains + 10)
Authority is the domain's position in harmonic centrality across the graph, rescaled to 0–100 — a rank, not a count, because a rank cannot be inflated by buying links; to move up you have to pass somebody. The divisor is logarithmic on purpose: dividing flat by outbound links would put whoever links to one single site at the top, which rewards obscurity rather than relevance.
Ahrefs' DR, Moz's DA and Majestic's Trust Flow are all closed formulas. This one is written above, computed from a public graph, and you can rebuild it yourself and get our exact numbers.
Check a thousand at once
This is the part every paid tool guards hardest, and the part that costs us nothing. Paste a list — one domain per line, or comma-separated, up to 1,000 — and get the referring-domain count and authority score for all of them, then take the table away as a CSV.
Your list never leaves the browser. Instead of sending it to us, the page downloads the slices of our index it needs — public static files — and does the matching on your machine. A short list pulls a few hundred kilobytes; a thousand names pulls most of the index, around 15 MB, once. After that every further lookup is instant and costs nobody anything. This is also why there is no bulk limit to raise: there is no meter to run.
What the same number costs elsewhere
| Service | What you get | Price |
|---|---|---|
| Semrush (SEO) | Backlink Analytics inside the SEO toolkit | €134.00 / month |
| Ahrefs (Lite) | Full backlink and referring-domain data in Site Explorer | €119.00 / month |
| Majestic (Lite) | Referring domains and referring IPs, Fresh Index (last 120 days) | €46.99 / month |
| Ahrefs (Starter) | Site Explorer with limited rows per report | €27.00 / month |
| Open PageRank (free tier) | A 0-10 score only — no list of referring domains. 30,000 domains a month, and it needs an API key | Free |
| This page | The qualified referring-domain count, computed from the public Common Crawl web graph | Free |
Prices read from each vendor's own pricing page on 2026-09-07. We link the page so you can check it yourself; they change them without telling us, and a price we cannot show you the source for is a price we do not print.
Where the limits actually are
We are not a crawler. Common Crawl publishes its web graph a few times a year, so this is a snapshot, not a live feed: a link built last week is not in here. It is domain-level — you get the sites that link to you, not the individual pages, and not the anchor text. There are no traffic estimates, because we do not have traffic data and inventing it is how a number ends up looking authoritative and being fiction.
If you need pages, anchors, freshness within days, and a crawler of their own, the paid tools in the table above genuinely do things this page cannot. What they also do is charge between €27 and €134 a month, hold the answer behind an account, and cap how many times you may ask.
The API, with no key
Same data, same endpoint this page uses. No key, no account, no rate limit, CORS open, so you can call it from your own site:
curl 'https://marcobics.pages.dev/api/domain?domain=example.com'It answers with the referring-domain count, the authority score, the list of
referrers, whether that list is complete, and — from RDAP, the public registry
protocol — whether the name is registered at all. Pass &rdap=0 to
skip the registry lookup and get an answer faster. If you build something with
it, we would rather you linked back than asked permission.
Free page, or the file
The tool above is free and stays free. The file is the same work done already, laid out, and yours offline — buy it if that is worth 23 euro of your time, not because the page held anything back.
This page
- Up to 100 referring domains, listed and ranked
- 1,000 domains at once, not one at a time
- An authority score, with the formula written down
- Unlimited lookups: no account, no API key, no cap
- All of it as CSV, and a free API with no key
The Expired Domain Field Guide: 15 Checks That Rejected 45%
- 3,412 expired domains already screened and ranked
- The archived page of each one, so you see what it was
- The scoring method, step by step, to redo it yourself
- The traps: link farms, recycled spam, fake authority
One payment, no account on this site, no renewal. Gumroad handles the checkout and the VAT; we never see your card.
Questions people actually ask
Is this really free, or free until I hit a wall?
Free. There is no account, no key, no daily cap and no upgrade button on this tool, and the reason is structural rather than generous: the answers are static files sitting on Cloudflare's edge, so your lookup costs us nothing whether you do one or ten thousand. What we sell is a different thing — a €23 file of 3,412 expired domains already screened — and you never have to look at it.
How does this compare to Ahrefs or Semrush?
Honestly: they crawl the web themselves, continuously, and index trillions of individual links with anchor text and traffic estimates. We read a public graph that is refreshed a few times a year, at domain level. For who links to this domain and how strong are they, we answer the same question free and uncapped. For anything page-level, live, or traffic-related, they are the tools and we are not pretending otherwise.
What does "qualified" mean in the count?
A link only counts if it comes from a domain in the top million of the graph by harmonic centrality. Without that filter the number is trivially gamed: we have seen fifteen domains sharing 52,876 identical referring domains, which is one link network counted fifteen times and looks fantastic in a report. The threshold throws that away.
Why do some domains return "fewer than 20"?
Because they have fewer than twenty qualified referring domains. We ship the slice above that line — 742,019 domains — and below it the absence is the answer, not a lookup that failed. We would rather say "under twenty" than show you a zero we did not measure.
Is the list of referrers complete?
Up to a hundred per domain. For 84% of the domains we cover that is the entire list, not a sample, and the tool tells you which case you are in. Ahrefs' free checker also stops at a hundred; the difference is what happens on your second lookup.
Can I use this data commercially?
The underlying graph is Common Crawl's, published openly. Our counts, scores and lists are derived from it and you are welcome to use them, including commercially. A link back is appreciated and not required. Do check the number against a second source before you spend real money on it — we would.
Do you log what I type?
No. There are no cookies, no analytics scripts and no accounts on this site. The domain you type goes to the edge to look up a static file and, unless you turn it off, to the public RDAP registry to ask whether the name is registered.
The other free tools
Same rules: no account, nothing stored, and the working shown.
Checking backlinks without paying for the data first
Everyone who has looked into SEO tooling has had the same afternoon. You want to know who links to a site — yours, a competitor's, one you are about to buy — and every answer costs between €27 and €134 a month, or arrives cut off at a line that exists to make you subscribe. Moz gives you roughly ten lookups. Ahrefs shows the first hundred backlinks and stops. Open PageRank will give you 30,000 domains a month, but wants an API key first, and gives you a score without the list. The data underneath all of it is not the hard part; the billing is.
The odd thing is that a large part of that data is public. Common Crawl has published a web graph for years — every domain, every link between domains, free to download. What it is not is usable: 9.4 GB of compressed edges and 2.45 billion rows are not something you open on a laptop to check one name. The paid tools are, to a real extent, selling you the fact that they did the processing.
So we did the processing. The graph sits on one machine in a flat in Milan that was already running anyway; counting the qualified in-degree of 15.5 million domains takes about twenty minutes, and building the reverse index — who links to whom, ranked — takes six. Both were paid for by a computer that would have been switched on regardless, which is why we can give the result away without a plan, a key or a counter. The list, the score, the CSV and the API cost us the same whether you use them once or a thousand times: nothing.
What we do sell sits one step further along, and only for one specific job. If you are buying expired domains, the count is where the work starts, not where it ends — a clean referring-domain profile is exactly what a spam network goes shopping for, and the name that looks best on this page is often the one with a casino in its past. That screening, on 3,412 domains, with the archived page of each one, is the €23 file. This tool is not a trailer for it. It is the thing we needed ourselves, and it is complete.