A couple of months ago I stumbled on a really interesting dataset, derived from the awesome Common Crawl.

That dataset was host-level PageRank from the Common Search project. This is a 112M host file with, as the name suggests, computated PageRank from the June 2016 Common Crawl. It’s great data but it’s not hugely accessible to most people – opening a 3.5GB file is not something you can do in Excel and remain sane.

So I set to work over a couple of weekends to turn it into something a bit more usable and am now pleased to introduce: OpenRank.io.

What is it?

OpenRank is a Domain Authority tool returning a simple 0-100 score. It can be used as a free (albeit less accurate) alternative to Moz DA, Ahrefs Rank and Majestic Trust Flow; but there are a few things that you probably need to know:

• OpenRank merges the 112M host-names into ~40M registrable root domain names.
• OpenRank fits a 100-point logarithmic scale to return a simple 0-100 score.
• There is no de-spamming step and so you should expect inflated numbers for bad domains.
• A host-level webgraph is going to be inherently less accurate than a page-level webgraph.
• Sites that block crawlers will have inflated PageRank (due to PR hoarding)
• OpenRank will be updated whenever a new PageRank dataset is released by Common Search, but is likely a few months out of date at any one time

As I already mentioned, OpenRank is completely free to use, but due to costs on my side there will be rate limits in place. You can make up to 1000 requests per day per IP to the HTTP service, and if you sign up for a free API key you can make up to 10,000 requests per day (and return up to 50 domains per request).

If you need higher rate limits, then just drop me a DM on Twitter: @bmilleare

Why not just use the free version of Moz API?

For detailed (eg. page-level) analysis, the Moz API is definitely the way to go and their metrics are some of the best in the industry. However the free version of their API has very restrictive rate limits. This makes it difficult to pull mass data quickly.

What next?

There are a few things I’d like to do to expand OpenRank’s usefulness – if you sign up for an API key you’ll hear about them first!