The top .io websites by PageRank belong to developers and software companies. GitHub Pages, documentation hosts and open-source projects lead, followed by SaaS tools for analytics, forms and privacy notices.

The .io ending is the country code of the British Indian Ocean Territory, but tech startups adopted it because "IO" reads like input/output.

500 sites · page 16 of 20
#WebsitePageRankLinking sitesGlobal rankCompare
376parkmobile.io7.451,10718,924Compare
377privacymanager.io7.451,29219,069Compare
3788b.io7.451,88519,312Compare
379metooo.io7.452,35119,383Compare
380imgku.io7.4433519,421Compare
381logz.io7.4468319,564Compare
382tigera.io7.4466019,572Compare
383yeoman.io7.4469719,576Compare
384expo.io7.4472419,582Compare
385rybbit.io7.4469119,584Compare
386brainstation.io7.4477819,597Compare
387skribbl.io7.4477619,607Compare
388packagecontrol.io7.4476319,611Compare
389postscript.io7.4481019,641Compare
390zeplin.io7.4492119,698Compare
391rdrr.io7.441,02219,757Compare
392notes.io7.442,79020,275Compare
393aje.io7.4347920,297Compare
394coderpad.io7.4338720,311Compare
395libraries.io7.4344120,320Compare
396perfmatters.io7.4352820,345Compare
397gogs.io7.4374320,396Compare
398wordlift.io7.4378420,405Compare
399liftoff.io7.4380120,411Compare
400elementary.io7.4379720,414Compare

Data: Open PageRank, data file October 2026. Domain data derived from Common Crawl. Not Google's own PageRank.

Why the top .io websites are widgets and hosts

Some .io services sit inside other websites: a review widget, a cookie banner or a status page. Every site that embeds one links back to it, so the score climbs fast even when few people visit the service itself.

Hosting domains like GitHub Pages also collect links for every project they host. That is why they rank above many famous apps.

Browse the top .io websites to find tools your own site may already use, and compare them in the checker.

Frequently asked questions

What does .io stand for?

It is the country code of the British Indian Ocean Territory. Tech companies like it because IO also means input/output.

Why is github.io at the top?

GitHub Pages hosts millions of project sites on github.io, and the links to all of them count for the whole domain.

Is a .io domain good for SEO?

Google treats .io like a generic ending, not a country site. The ending itself does not raise your score; links do.