How the directory is built, and how often it is wrong
Every campus row has a source. Every capacity figure says who states it. We check the rows against independent sources, count the errors, and publish the result here, including where we fall short.
The short version
In the September 20, 2026 audit, the share of capacity (MW) figures found wrong was 6.3% when wrong means a source contradicts the figure, 17.5% when a power, utility-contract, program or phase figure filed as the campus total also counts as wrong, and 42.9% when only a word-for-word statement of the campus load counts as right.
We have not reached our own pass mark yet. The bar we set is 5% wrong or less, with the top of the confidence interval at 10% or less. Capacity misses it on all three ways of counting.
Estimated cost is the weakest field we measured on a real sample: 13.9% wrong (5 of 36). Each of those errors was a modelled figure sitting where the developer had published its own.
Every error the audit confirmed was corrected through a sourced proposal. The next audit is due late October 2026.
What a row is
A row is one named data center campus. It is not every building on the site. When a campus is built in phases, each phase hangs off its campus row, and the campus is counted once.
We also track power plants, chip fabs and things that are not campuses, like a supercomputer inside another operator's hall or a cloud region. They have pages, but they never count toward campus, state or MW totals. Coverage is named campuses, mostly the large ones.
Where a number comes from
Every row links at least one source: an article, a press release, a planning record, a utility filing or the company's own page. An aggregator listing is never the source of a fact.
Nobody outside the builder can measure a campus's megawatts. So we never call a figure official. We show who said it, and when.
- Filed: a record states the figure (an SEC filing, a permit or planning record, or a utility filing).
- Stated: the developer or the press states the figure.
- Estimated: no source states the exact figure, so it is modelled or inferred. That includes Epoch AI's IT-power model. Lists and rankings mark these figures "est."
Filed and stated figures carry an "as of" date, the date of the newest source that states them. A rule sets the label: a figure only counts as stated when a source quote gives that exact number for the campus itself.
How it stays right
- Every change a person makes goes through a proposal that names one source and quotes it. It is checked before it is applied, and nobody edits a row by hand.
- A correction locks the field, so the nightly scrape cannot swap a sourced value for a modelled one.
- A daily check runs over every number the site shows, including the figures on this page.
- Sources for the Tier 1 campuses are saved to the Internet Archive's Wayback Machine.
- Possible duplicates are flagged by rule, and pairs confirmed to be different campuses are recorded as checked.
How accurate it is, measured
On September 20, 2026 we audited our Tier 1 rows: the 285 campuses that matter most, meaning the largest by MW plus every US campus being built. We checked all 25 of the largest and a random draw of 60 more, drawn with a fixed seed so it can be repeated.
Each field was checked against one independent second source, found by search rather than taken from the row. Each rate comes with a 95% confidence interval (the Wilson method).
Capacity, counted three ways (same 63 figures)
- Contradicted by a source: 6.3% (4 of 63, 95% interval 2.5 to 15.2%). A source contradicts the figure.
- Plus scope errors: 17.5% (11 of 63, 95% interval 10.0 to 28.6%). Also counts a power, utility-contract, program or phase figure filed as the campus total.
- Word-for-word only: 42.9% (27 of 63, 95% interval 31.4 to 55.1%). Only a word-for-word statement of the campus load counts as right.
Of the figures that held up, 23 rest on a ceiling, a floor, a plan or a power figure rather than a stated campus load, and those rows are labelled estimated. Another 19 capacity figures could not be checked at all, because no independent source states them.
Every field, all 108 audited rows
This table includes 23 rows picked because an earlier audit had corrected them. Those rows go wrong more often (18.2% of their capacity figures were wrong), so the table leans pessimistic.
| Field | Wrong | Rate | 95% interval | Within 5%? |
|---|---|---|---|---|
| Capacity (MW) | 9 of 84 | 10.7% | 5.7 to 19.1% | No |
| Status | 0 of 95 | 0.0% | 0.0 to 3.9% | Yes |
| Location | 0 of 35 | 0.0% | 0.0 to 9.9% | Yes |
| Developer | 2 of 44 | 4.5% | 1.3 to 15.1% | Yes |
| Expected completion | 1 of 33 | 3.0% | 0.5 to 15.3% | Yes |
| Tenant | 1 of 14 | 7.1% | 1.3 to 31.5% | No |
| Estimated cost | 5 of 36 | 13.9% | 6.1 to 28.7% | No |
| Campus name | 3 of 3 | 100.0% | 43.8 to 100.0% | No |
Tenant: Only 14 rows had a tenant to check, so this rate is loose.
Campus name: Only 3 names were checked and all 3 were wrong. The next audit checks the name on every row.
Found an error?
Open the campus page in the directory, expand "sources" at the bottom, and use "Suggest a correction or add a source". Include a link that states the right figure. You can also email hello@datacenterindex.ai.
Licences and credit
- Epoch AI, Frontier Data Centers, CC BY 4.0.
- AI Data Center Index (SheetGenius, Inc.), CC BY 4.0. We use its public browse pages only.
Both credits travel with every export row and every API response. More on the site and its house rules: About.