OpenAI funding: Every round, investor, and valuation (2026)

Most people know OpenAI through ChatGPT, the chatbot that roughly a billion people now use every week. Behind it sit the GPT models, the Codex coding agent, and an API that thousands of companies build their own products on. All of it runs on rented computing power, and that computing power is what OpenAI's investors are really paying for.

OpenAI has raised more than $180 billion across a string of donations, Microsoft deals, and funding rounds. Its latest round, closed in March 2026, was the largest private financing on record and valued the company at $852 billion.

The way it got there says a lot about how frontier AI gets built. Early money came from wealthy donors. Then came a single tech giant. Now OpenAI's biggest backers are the same companies that sell it chips and cloud capacity. Let's dive into OpenAI's funding history.

OpenAI's funding falls into three eras: a nonprofit funded by donors, a research lab funded by Microsoft, and a commercial company funded by the rest of the industry. Each era ended when the money ran short of what the next generation of models needed.

OpenAI launched in December 2015 with a headline pledge of $1 billion. The backers included Musk, Altman, Hoffman, Peter Thiel, Jessica Livingston, Amazon Web Services, and Infosys.

The cash that actually arrived was far smaller. Tax filings reviewed by TechCrunch show the nonprofit received $133.2 million through 2021. OpenAI says less than $45 million of it came from Musk.

When Musk held back funding in 2017 during talks about a for-profit arm, Hoffman covered salaries to keep the lab running. Musk left the board in early 2018.

Donations could not pay for large-scale model training. In 2019, OpenAI created a "capped-profit" subsidiary, a company whose investors could earn up to 100 times their money and no more.

Microsoft became the first big investor that July, and Azure became OpenAI's exclusive cloud. Microsoft invested again in 2021, then made a multiyear commitment in January 2023, two months after ChatGPT launched. Reuters puts Microsoft's cumulative investment at about $13.8 billion.

In between, OpenAI let employees sell shares to outside investors. These sales raised no new money for the company, but they set prices. A Thrive-led tender offer completed in February 2024 valued OpenAI at about $86 billion, triple the price from a year earlier.

The modern funding story starts in October 2024. Thrive led the round, and Microsoft, Nvidia, and SoftBank joined. The money came as convertible notes, debt that only turned into shares if OpenAI restructured into a normal for-profit company.

A day later, OpenAI added a revolving credit line from nine banks led by JPMorgan and Citi. OpenAI has never drawn on it, even after it grew to about $4.7 billion in 2026.

SoftBank's 2025 round came with a catch. Its commitment would fall by half if OpenAI did not finish restructuring by the end of 2025.

OpenAI completed the recapitalization in October 2025. SoftBank paid its final $22.5 billion in December, and the round closed slightly above its $40 billion target once co-investors were counted.

The 2026 round started with three companies that sell OpenAI its infrastructure. Amazon, Nvidia, and SoftBank committed $110 billion in February.

By the close on March 31, the round had grown by another $12 billion. That came from Microsoft, a long list of funds including Blackstone, Sequoia, and Temasek, and more than $3 billion from wealthy individuals who bought in through their banks.

Two smaller deals sit alongside the rounds. Disney agreed to invest $1 billion in December 2025 as part of a deal to license its characters to Sora, OpenAI's video app. OpenAI shut the Sora app down three months later.

In August 2026, OpenAI bought back about $7 billion of employee shares at the March price. Staff got to cash out without the company taking on new investors.

OpenAI's valuation rose about 29-fold in just over three years. Each step followed a jump in revenue and a bigger round.

The price nearly doubled between the 2024 and 2025 rounds, then almost tripled by 2026. Revenue grew faster than that.

OpenAI booked $3.7 billion in revenue in 2024 and $13.1 billion in 2025. By late September 2026, its annualized revenue was nearing $70 billion.

In September 2026, investors floated a round at more than $1.2 trillion. Bloomberg reported early talks to raise at least $30 billion at about $1.4 trillion as bridge money ahead of an IPO. OpenAI has not confirmed either figure.

The October 2025 recapitalization changed who holds that value: the nonprofit OpenAI Foundation kept control with about 26% and Microsoft took about 27%. The full breakdown of who owns OpenAI and how control is split covers the rest.

OpenAI's biggest checks no longer come from venture funds. They come from suppliers, and each one attached a supply deal to its money.

Microsoft backed OpenAI when it was a research lab with no product. After the 2025 recapitalization, it held roughly 27% of the company, a stake then worth about $135 billion.

The recapitalization also rewrote the partnership. Microsoft gave up its right to be OpenAI's first choice for computing. In return, OpenAI committed to buy another $250 billion of Azure cloud services, and Microsoft kept access to OpenAI's models and products through 2032.

Microsoft's own widely held ownership makes for an odd pairing. A public company owned by index funds now holds a quarter of the most valuable private AI lab.

SoftBank went from a $500 million check in 2024 to leading the 2025 round and putting $30 billion into the 2026 round. Reuters reports it will own about 13% of OpenAI once its final payment lands.

SoftBank is borrowing to get there. It sold more than $11 billion of bonds in September 2026 to fund its last tranche, which is a large bet for a company with SoftBank's founder-led ownership. SoftBank is also OpenAI's partner in Stargate, a data center venture with Oracle and MGX.

Amazon's $50 billion was the largest single check in the 2026 round. It came with a cloud deal attached.

OpenAI expanded its existing AWS contract by $100 billion over eight years and committed to use Amazon's Trainium chips. AWS also became the only outside cloud allowed to sell OpenAI's Frontier platform for enterprises.

Part of Amazon's money was meant to arrive only if certain conditions were met. Amazon paid all of it within months anyway, a sign of how much Amazon's cloud business wants OpenAI's workloads.

Nvidia invested $30 billion in 2026. That replaced a 2025 plan to invest up to $100 billion, which Nvidia's CEO later said was "not in the cards."

The deal gives OpenAI dedicated capacity on Nvidia's newest Vera Rubin systems for both running and training models. In practice, Nvidia's money helps OpenAI buy more Nvidia chips, a circular flow that sits at the center of Nvidia's chip-selling business.

Thrive Capital is OpenAI's most consistent venture backer. It led the 2024 round with about $1.2 billion and has joined every round since.

Khosla Ventures backed the capped-profit company in 2019. Other repeat names include Altimeter, Coatue, Fidelity, Dragoneer, MGX, Sequoia, Andreessen Horowitz, and T. Rowe Price.

OpenAI spends its funding on computing power, people, and acquisitions. Computing power is by far the largest.

OpenAI owns no data centers. It rents capacity from nearly every supplier in the market: Microsoft, Oracle, Amazon, CoreWeave, and Cerebras for cloud, plus chip deals with Nvidia, AMD, and Broadcom.

Oracle's deal alone runs to about $300 billion over five years, and the AMD deal gives OpenAI warrants for about 10% of AMD.

Sam Altman once described about $1.4 trillion of commitments. In February 2026, OpenAI reset expectations with investors to about $600 billion of compute spending through 2030. In April, it pulled out of planned Stargate sites in the UK and Norway.

Leaked 2025 financials show OpenAI spent $19.2 billion on research and development, more than its total revenue that year. Most of that pays for training new models and for the researchers who build them, including large stock awards.

Several senior executives left in the summer of 2026, and employees have been able to sell shares in tender offers roughly once a year.

OpenAI's largest deal was io, Jony Ive's hardware startup, for about $6.5 billion in 2025. It also paid about $1.1 billion in stock for Statsig, a product-testing company.

Most other deals are small team purchases. OpenAI closed six of them in the first quarter of 2026 alone.

Projections reported by The Information show negative cash flow of about $25 billion in 2026, rising to $85 billion in 2028, before OpenAI turns cash-flow positive around 2030.

A July 2026 investor deck reported by the FT suggested the $122 billion round would last until around 2028. The revenue side of that equation is covered in how OpenAI makes money.

Businesses are now OpenAI's main growth engine. CFO Sarah Friar told investors in August 2026 that enterprise revenue had passed consumer revenue, led by Codex and OpenAI's work tools, which reached about 20 million weekly users. Ads are the second bet: launched for free US users in January 2026, they hit a $1 billion annualized run rate by August.

OpenAI released its GPT-6 models in September 2026, after shutting the standalone Sora app in March and folding its Atlas browser into ChatGPT in August. ChatGPT and Codex now carry the product line. Its first device with Jony Ive will not ship before the end of February 2027.

OpenAI confidentially filed to go public in June 2026, and Sam Altman has said listing in 2026 would be ill-advised, so a bridge round at about $1.4 trillion may fund the compute bill until then. The biggest risks are Anthropic's revenue model, which overtook OpenAI on quarterly revenue in 2026, and compute contracts that assume revenue keeps compounding. Anthropic's $65 billion Series H in May 2026 valued it at $965 billion, above OpenAI's March price.

OpenAI has raised more than $180 billion in equity since 2015. Most of it came in three rounds: $6.6 billion in October 2024, $41 billion in March 2025, and $122 billion in March 2026. It also has a revolving credit facility of about $4.7 billion that it has not drawn.

OpenAI's largest investors are Microsoft, SoftBank, Amazon, and Nvidia. Other backers include Thrive Capital, Khosla Ventures, Andreessen Horowitz, Sequoia, Altimeter, Coatue, Fidelity, Dragoneer, MGX, T. Rowe Price, D. E. Shaw, TPG, and Disney.

OpenAI was valued at $852 billion after its $122 billion round closed in March 2026. An August 2026 employee share buyback used the same price. In September 2026, investors discussed a new round at $1.2 trillion to $1.4 trillion, which had not closed.

No. OpenAI is private. It confidentially filed for an IPO in June 2026, but Sam Altman has said it will not go public in 2026, and the company has pointed to 2027.

The nonprofit OpenAI Foundation controls OpenAI and held about 26% after the October 2025 recapitalization. Microsoft held about 27%, and employees and other investors held the rest. Later rounds diluted those stakes, and SoftBank is expected to own about 13%. Sam Altman holds no equity.