The AI capex tracker

Why this number matters

Capital spending by a handful of companies is the single most important number for AI investors, whatever they own. It is the revenue of the chip, memory, networking, server and power companies, so when these buyers raise or cut their plans, every layer of the stack feels it within a quarter or two. It is also the cost that the buyers’ own shareholders have to earn back.

This tracker uses only reported figures: cash paid for property and equipment, from each company’s cash-flow statement, aligned to calendar quarters so companies with different fiscal years can be added up. It updates when the companies file their 10-Qs and 10-Ks, and it doesn’t use guidance or estimates.

The build-out, year by year

Seen by calendar year, the build-out has three phases. In 2021 and 2022 the five buyers spent $131B and $158B, mostly on the cloud and consumer businesses they already had. 2023 was a pause: $154B, as the companies digested pandemic-era capacity and ChatGPT’s launch had only just begun to change their plans. From 2024 the spending climbed steeply, reaching $412B in 2025, and the latest four quarters are higher again.

The cash-flow column shows how the phases were paid for. Operating cash flow also grew strongly, which is what allowed the first stage of the surge without borrowing. The latest quarters are different: capex has kept rising faster than cash flow, so the ratio between them, low through 2023, now sits near its highest. The next phase of the build-out depends on whether cash flow catches up or the companies decide the spending is worth funding from their balance sheets.

Company by company

Microsoft spent $136B over its latest four quarters to September 30, 2026, +97% on the four before, 69% of its operating cash flow. It reports $683B of remaining performance obligations. It also discloses $329B of leases signed but not yet started.

Amazon spent $173B over its latest four quarters to June 30, 2026, +61% on the four before, 107% of its operating cash flow.

Alphabet spent $160B over its latest four quarters to September 30, 2026, +105% on the four before, 89% of its operating cash flow. It reports $568B of remaining performance obligations. It also discloses $131B of leases signed but not yet started.

Meta spent $104B over its latest four quarters to September 30, 2026, +66% on the four before, 78% of its operating cash flow. It also discloses $356B of leases signed but not yet started.

Oracle spent $75.7B over its latest four quarters to August 31, 2026, +176% on the four before, 161% of its operating cash flow. It reports $664B of remaining performance obligations. It also discloses $260B of leases signed but not yet started.

CoreWeave spent $20.6B over its latest four quarters to June 30, 2026, +140% on the four before, 298% of its operating cash flow. It reports $104B of remaining performance obligations. It also discloses $35.5B of leases signed but not yet started.

What capex leaves out

Cash capex leaves out two kinds of commitment. Equipment acquired under finance leases is paid for over time rather than up front, and several buyers use them heavily; it shows up in the cash-flow statement as lease principal payments rather than capex. Leases signed for data centers that aren’t built yet don’t appear anywhere in the financial statements, only in the notes. Both are real commitments, and the second is now larger than a year of capex for the group.

Backlog, reported as remaining performance obligations, is the other side of the ledger: contracts customers have signed for capacity the buyers are building. Large backlogs at Microsoft, Oracle, Alphabet and CoreWeave are the reason they give for spending so much. A backlog that grows as fast as capex supports the spending; one that stalls while capex keeps rising would be a warning.

Using the tracker

The tracker is the top of the map: the spending every other page follows. To see where the dollars land and who keeps them, go to following the money. To see the suppliers that depend on this spending, start with the chips, memory and power layers, whose revenue tracks these numbers with a lag of a quarter or two.

A useful habit after each earnings season: compare each buyer’s new quarterly capex with the quarter before and the same quarter a year earlier, then check whether its cloud segment grew faster or slower than its spending. Two or three quarters in which spending grows and cloud revenue doesn’t keep pace is the earliest sign, available to anyone, that returns on the build-out are falling. The reverse, cloud growth outpacing capex for several quarters, would be the clearest sign that the spending is starting to pay.

What to watch each quarter

• Each company’s capex guidance on its quarterly call, then the reported figure in the 10-Q a few weeks later.
• Capex as a share of operating cash flow: above 100% for the group means the build-out depends on borrowing.
• Finance lease principal payments and leases not yet commenced, for the spending capex leaves out.
• Remaining performance obligations, to see whether contracted demand keeps pace.
• Depreciation as a share of revenue, as the spending reaches the income statement.

To turn these numbers into the revenue they imply, use the capex payback calculator; to see what they mean for future depreciation, the useful-life calculator. Where the money lands is on following the money.