What Is a Data Center Directory — and How to Use One

Ask ten people in this industry what a data center directory is and you will get ten answers. Some picture a list of cities with facility names underneath. Some picture a broker who calls you within an hour of filling in a form. Some picture a spreadsheet a colleague keeps and never quite updates.

All three exist. Only one of them is actually a directory, and knowing the difference matters when you are trying to shortlist somewhere to put your racks.

What a data center directory actually is

A directory is a structured, searchable record of facilities and the companies that run them. Its job is to answer "what exists, where, and who operates it" — and to keep answering that as the market changes. It is reference infrastructure, not a sales channel.

That distinguishes it from three things it often gets confused with:

• A broker. Brokers are paid on placement, so their list is the set of operators they have agreements with. That can be genuinely useful. It is not comprehensive, and it is not neutral.
• A marketplace. Marketplaces sell capacity. The inventory shown is the inventory for sale this quarter, which is a small slice of what physically exists.
• A map. A map shows you where things are. A directory tells you what they are. The good ones do both, but plotting pins is the easy half.

The practical test is coverage. A directory should list facilities whether or not they have space to sell, whether or not they pay to appear, and whether or not anyone has claimed the record. Data Center Planet currently holds 9,781 published facilities across 166 countries and 3,517 cities, 9,552 of them geocoded and plotted. That includes plenty of sites with nothing available and no commercial relationship with us, because leaving them out would make the picture wrong.

What good directory data looks like

A facility name and a city is a start. It is not enough to make a decision with. The fields that actually change a shortlist are the dull, specific ones:

• Power. Total and available capacity in MW, power per rack, redundancy topology (N, N+1, 2N). Most capacity conversations end here.
• Space. Net technical space, rack and cabinet counts, what is genuinely available versus contracted.
• Efficiency. PUE, cooling method, renewable supply. Increasingly a procurement gate rather than a nice-to-have.
• Resilience. Tier level, generator and UPS arrangements, fire suppression.
• Compliance. ISO 27001, ISO 9001, SOC 2, PCI DSS. If you are in a regulated sector this filters the list before anything else does.
• Connectivity. Carriers on site, internet exchange presence, whether the building is carrier-neutral.

Be sceptical of a directory where every record is complete. Real facility data is patchy — operators publish what they want to publish, and some publish very little. A directory that shows gaps honestly is more trustworthy than one that has quietly filled them in.

Three ways buyers actually use one

In practice, almost all directory use falls into three jobs.

Building a colocation shortlist. You know roughly where you need to be and roughly how much power you need. You filter by market, then by capacity and certification, and come out with eight or ten candidates worth contacting. The directory's job is to get you from "somewhere in Frankfurt" to a named list without a dozen phone calls.

Checking interconnection and latency. Here the question is not "is there a data center in this city" but "what can I reach from it". That means carriers, exchange points, and increasingly the subsea routes that determine whether your traffic between regions takes 90ms or 140ms. This is the job most directories handle worst.

Market research. Analysts, investors and operators planning expansion want the shape of a market rather than a specific building: how many facilities in a country, who owns them, where the clusters are, what is under construction. Coverage breadth matters far more than depth of any single record. For reference, the markets with the deepest coverage on Data Center Planet are the United States with 3,858 facilities, then Germany at 446, the United Kingdom at 429, France at 376 and Brazil at 352.

How to judge whether a directory can be trusted

Four questions, and they are worth asking of any directory including this one.

When was this record last touched? Facilities change hands, get renamed, expand and close. A directory that cannot tell you how fresh a record is cannot tell you whether it is right.

Can the operator correct it? The most reliable source for a facility's details is the company running it. If there is no route for an operator to claim their record and fix it, errors are permanent. Ours is free, and the operator keeps control of the profile afterwards.

Does paying change your visibility? This is the one to press on. If appearing at all requires payment, you are reading an advertising inventory with a directory's name on it. Listings on Data Center Planet are free and unrestricted. Advertising buys additional placement — a pin highlight, a promoted card — and never gates the underlying profile.

Where is the coverage thin? Every directory is biased toward the markets it was built in. Ours is strongest across North America and Western Europe and thinner in parts of Africa, Central Asia and the Pacific. Knowing where the gaps are is part of using the data properly.

The dimension most directories miss

Facilities do not operate in isolation. They sit on a physical network, and for anything latency-sensitive or multi-region that network decides the shortlist as much as the building does.

This is why we plot 711 submarine cables on the same map as the facilities. Choosing between two sites in Mumbai is a different exercise when you can see which cable systems land nearby and where they go. Most directories treat connectivity as a text field listing carrier names. Seen geographically, it changes decisions.

The same logic covers industry events. Procurement is still a relationship business, and knowing which conference the operators you are evaluating will attend is practical information. We track 61 of them in a public events calendar.

Listing or claiming a facility

If you operate a facility, your record probably already exists — most of the directory was built from public infrastructure data, not from submissions. That means it may be incomplete or out of date, and you are the only one who can fix it properly.

Create an account and claim it. It costs nothing, there is no restriction on the core profile, and once it is yours you can add specifications, photographs, certifications and contact routes. If the facility is not listed at all, add it the same way.

For a direct comparison with the older directories in this space, read Data Center Planet vs DataCenterMap. To start searching, the interactive globe is the fastest way in, or browse by country and city if you already know the market.

Frequently asked questions

What is a data center directory?
A structured, searchable record of data center facilities and the companies operating them, covering location, ownership, power, space, certifications and connectivity. A good one lists facilities regardless of whether they have capacity for sale or a commercial relationship with the directory.

How is a directory different from a colocation broker?
A broker earns commission on placement, so their list reflects the operators they work with. A directory aims for complete coverage of a market, including facilities with nothing available.

Is there a free data centre directory?
Yes. Data Center Planet is free to search with no account required, and free for operators to list and claim their facilities.

How many data centers are there worldwide?
Nobody knows precisely, because there is no central register and definitions vary on whether to count enterprise server rooms and edge sites. Data Center Planet publishes 9,781 facilities across 166 countries, which is a floor rather than a total.

Can I add my data center to the directory?
Yes, free of charge. Create an account to add a new facility or claim one already listed.