About
About LinkIsFlow and the link-flow view of SEO
LinkIsFlow is a small, opinionated slice of a larger backlink data service. We cover the external half of the link-flow picture and say so.
- domains in the index
- 181,132,097
- domain-to-domain links
- 2,774,625,913
- backlinks indexed
- ~798.5 billion
- one credit
- $0.0001
What we do
We run a developer REST API and a free online explorer for backlinks, referring domains, anchor text, top pages and a 0 to 100 Domain Rating. Responses are JSON.
The data comes from our own crawler and our own link index. It refreshes roughly once a month.
This site is written for technical SEOs who study how equity moves through a site: internal linking, depth, hubs and the points where outside links enter. That is a narrow reader. We prefer a narrow reader to a vague one, since it keeps every page honest about who it is for. If you work on entry pages and internal paths, you are who we had in mind.
What we skip, on purpose
We do not map your internal links. Use a site crawler for that, such as Screaming Frog or Sitebulb, and join its export to ours.
We do not do keyword research, rank tracking or daily-fresh crawling either, and for those Ahrefs and Semrush are the fuller products. Our Domain Rating is our own metric, built from a public formula, and it is not the same number as Ahrefs DR or Moz DA.
The pages here are written by the LinkIsFlow research team. Examples with numbers are marked as examples, and we do not publish customer stories.
How the pieces fit
Think in layers. At the bottom sits the link graph, which holds 181,132,097 domains and 2,774,625,913 domain-to-domain links, plus about 798.5 billion backlinks. Above it sits a REST API, and above that a free explorer for quick looks.
Four actions are free and need no key: domain, overview, stats and suggest. The rest are priced from 1 credit to 3 credits, and a call is billed once whatever the number of rows.
Sign-in is by Google account only. A new account starts with $100 of free credit, which is 1,000,000 credits, and later top-ups are paid in USDT on TRC-20 from the account page.
Why so plain? Simple pricing, and a plain page on entry points too. Because a cost you can predict is a cost you can plan around. The cost table shows every price in one place.
How we write the guides
Each guide starts from a question that technical SEOs keep asking: how deep is too deep, which page should be the hub, what happens to links during a move. We answer with a method first.
Where a number is invented to explain a method, the page says so in plain words, and you will find it near the top. Real dates, such as Google's core updates, are named with their month and year.
We also try to say where a guide stops. A page about crawl depth cannot measure your depth for you, since that needs a crawl of your own site. Say so early. The reader loses less time, and nobody is misled in 2026 or later.