OpenAI

Maker of ChatGPT, GPT-5, Sora and the OpenAI API. Closed a record $122B Series H in March 2026 (led by Amazon, Nvidia, SoftBank) at an $852B post-money valuation — the largest private funding round in history. Revenue run rate hit ~$24B by March 2026.

AI🇺🇸 United StatesFounded 2015PPU equityopenai.com ↗

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Reviewed May 18, 2026 (8d ago)

Current estimate

4 methods · May 18, 2026High confidence (66%)

$761.5B

range $609.9B – $913.2B

Implied per-share: $514.6 · vs last primary -11%

This estimate reflects what informed investors are paying on secondary markets like Hiive and Forge — not the 409A valuation on your grant letter.

Last primary round

$852B

Series H (close) · 2mo ago

Secondary signal

$853.0B

Forge · 2026-04+0%

Sourced from Forge/Hiive public data. Full order books require a paid subscription; figures shown are best-effort from public disclosures.

Headcount

5,500

employees · LinkedIn+72%

LinkedIn count — directional proxy only. Historical figure sourced via Wayback Machine; treat ±15% as normal variance.

Revenue (est.)

$24.0B

annual run rate · est.

Complete company data

Every input we use, where we got it from, and how much we trust it.

Field	Value	Source	Confidence
Company fundamentals
Sector	AI	Editorial classification	high
Headquarters	🇺🇸 United States	Company website · Crunchbase	high
Founded	2015	Company website · Wikipedia	high
Website	openai.com	Direct	high
Latest primary round
Post-money valuation	$852B	Bloomberg Mar 2026	high
Round name	Series H (close)	Bloomberg Mar 2026	high
Date	2026-03-31 (2 months ago)	Bloomberg Mar 2026	high
Lead investor	Amazon / Nvidia / SoftBank	Bloomberg Mar 2026	high
Amount raised	$122.0B	Bloomberg Mar 2026	medium
Capitalization
Total fully-diluted shares	1,480M	SEC Form D · secondary price math · cap-table leaks › notes Public total fully-diluted share count: estimated from SEC Form D filings, secondary-market pricing math (implied valuation ÷ price per share), and leaked cap-table summaries. Considered the lowest-confidence input.	low
Implied share price (latest primary)	$515	Valuation × 1000 / share count (= $852B ÷ 1480M)	medium
Primary equity type granted	PPU	Public reports of company equity practices	high
Financials
Annual revenue (est.)	$24,000M	Sacra · The Information · press leaks › notes Annual revenue: best public estimates from Sacra, The Information, WSJ leaks, or company-stated ARR. Where official, we cite the source on the funding round.	medium
EV / Revenue (implied)	35.5x	Computed from valuation ÷ revenue	medium
Headcount
Employees (now)	5,500	LinkedIn — current company page count › notes Headcount: LinkedIn 'Company' page employee count, taken now and approximately 12 months ago via the Wayback Machine. Treat as a directional proxy for revenue growth, not a hard number.	medium
Employees (12 months ago)	3,200	LinkedIn via Wayback Machine	medium
12-month headcount growth	+72%	Computed	medium
Methodology inputs
Sector ETF proxy	BOTZ	Editorial choice — most representative public ETF › notes Sector ETF: editorial choice of the most representative public-market proxy. Annual return: 3-year trailing average from Yahoo Finance, refreshed quarterly.	medium
ETF annual return (trailing 3-yr)	15%	Yahoo Finance · refreshed quarterly	medium

Funding history

Primary rounds reported in Bloomberg, WSJ, TechCrunch, Reuters, or SEC Form D filings (efts.sec.gov). Linked per round below.

Valuation progression (equity rounds)

Valuation progression · equity rounds

$852Blatest · Series H (close)

Total growth

61×

Our estimate

$762B

Primary round

Down round

Our estimate

Series H (close)+1%2026-03-31

$852.0B

Led by Amazon / Nvidia / SoftBank · raised $122.0B

Source: Bloomberg Mar 2026

Series H (open)+68%2026-02-27

$840.0B

Led by Amazon / Nvidia / SoftBank · raised $110.0B

Source: TechCrunch Feb 2026

Secondary tender+67%2025-10-15

$500.0B

Led by Thrive Capital · raised $6.6B

Source: Bloomberg / WSJ Oct 2025

Series G+91%2025-03-31

$300.0B

Led by SoftBank · raised $40.0B

Source: Reuters Mar 2025

Series F+441%2024-10-02

$157.0B

Led by Thrive Capital · raised $6.6B

Source: WSJ Oct 2024

Strategic+107%2023-01-10

$29.0B

Led by Microsoft · raised $10.0B

Source: Bloomberg Jan 2023

Series C2021-01-01

$14.0B

Led by Microsoft · raised $1.0B

Source: TechCrunch

Secondary market signals

Secondary market signals: bid/ask/trade indications from Hiive (hiive.com), Forge Global, Caplight Index, and tender prices reported in the press.

Implied valuation over time

Implied valuation · secondary market

$853B+297% vs first recorded

Trade

Bid

⚠

Forge and Hiive publish aggregated market data publicly, but full order books, individual bids/asks, and confirmed trade prices require a paid account. The figures below are sourced from their public summaries, press-reported tender prices, and SEC disclosures. They represent the best publicly available signal — not a guaranteed executable price.

Date	Type	Source	Price / share	Implied valuation
2026-04-22	trade	Forge	$576	$853.0B
2026-02-10	trade	Hiive	$348	$515.0B
2025-12-05	bid	Forge	$320	$474.0B

View live indications: Hiive ↗ · SEC Form D filings ↗

Public peer comparables

Public peer comparables: editorial selection of public companies with the closest business model. EV/Revenue and growth from public 10-Q filings and Bloomberg, refreshed quarterly.

Ticker	Company	EV / Revenue	Revenue growth	As of
CRWD	CrowdStrike Holdings, Inc.	35.09x	+23%	2026-05-20
DDOG	Datadog, Inc.	21.55x	+32%	2026-05-20
MDB	MongoDB, Inc.	10.66x	+27%	2026-05-20
NET	Cloudflare, Inc.	32.81x	+34%	2026-05-20
NVDA	NVIDIA Corporation	20.57x	+85%	2026-05-20
PLTR	Palantir Technologies Inc.	62.81x	+85%	2026-05-20

Confidence breakdown

How much we trust each of the four valuation methods for this specific company, and why.

Method A — Peer-multiple

weight 25%→ $753.9B75% confidence

Growth-weighted peer EV/Revenue: 34.9x → 10% private-company discount → 31.4x on $24000M revenue

Method B — Secondary-implied

weight 45%→ $587.7B55% confidence

Recency-weighted average of 5 secondary indications (180-day decay)

Method C — Primary time-decay

weight 20%→ $909.0B82% confidence

$852B round (2026-03-31) × 1.08× growth × 0.99× multiple decay over 0.2 years

Method D — Sector momentum

weight 10%→ $870.3B58% confidence

$852B × (1 + 15% p.j.)^0.2yr = $870.3B via BOTZ ETF-proxy

Overall confidence

66%

Weighted average of the four methods. Above 65% is high, 40–65% medium, below 40% low.

High

Worked example for an employee

A concrete walk-through using a hypothetical employee profile. Same engine the calculator uses — try it with your real numbers.

Profile: a hypothetical employee who joined OpenAI 24 months ago (2024-05-26) with 2,000 units, on the standard 4-year vesting schedule with a 1-year cliff.

Vesting

1,000 of 2,000

50% vested at month 24

Implied share price (mid)

$515

weighted average of 4 methods

Gross vested value

$514,558

vested shares × implied price

Net value

$514,558

no strike, gross = net

Tax (rough)

$150,470

US federal only · AMT risk: low

What if the next round is…

Up round +30%

$581,675

New round at +30% valuation, 15% new shares issued

Down round −30%

$300,159

New round at −30% valuation, 20% new shares (higher dilution in distress)

Secondary today

$437,375

Sale on the secondary market at the typical 15% discount to the mid estimate

These numbers come from the same engine as the live calculator. Walk through with your own grant: use your real numbers →

Transparent assumptions

What we assumed where exact data isn't available. If any of these don't match your situation, the numbers above will be off.

Fully-diluted share count

1480M shares

We don't have authoritative cap-table access for private companies. The number above is reconstructed from SEC Form D filings, secondary-market price-vs-valuation math, and leaked share-class summaries. Actual fully-diluted count (including unvested option pool and SAFEs) may differ by 5–15%.

Common-stock waterfall

1.0× to common

We assume a clean common-stock outcome — i.e. preferred-share liquidation preferences and ratchets do not extract value before common. In a down-exit, this assumption can be very wrong: preferred stack can take 30–70% of proceeds.

Private-company illiquidity discount

10% off public peers

Applied to Method A (peer-multiple). Per-company because category leaders with deep secondary markets and a clear IPO path warrant a smaller discount than early-stage names. The literature range is 10–35%; for OpenAI we use 10% based on secondary-market depth, valuation history, and proximity to liquidity.

Revenue growth assumption (Method C)

60% YoY

Compounded forward from the last primary date to today to estimate the company's value drift. Set per-company based on disclosed or reported ARR trajectory. Method C is further capped at 1.3× the most recent secondary trade (if any) to stop runaway extrapolation when revenue growth outpaces what the market is actually paying.

Sector ETF momentum (Method D)

BOTZ @ 15%/year

Method D applies the trailing return of BOTZ as a market-proxy adjustment to the primary valuation. Crude — meant as a tiebreaker when peer and secondary data conflict, not as a primary signal.

Outlier auto-downweight

Methods >50% from median get ½ weight

Robust-statistics safety net: any method whose output strays more than 50% from the median of the other three methods has its confidence weight halved when computing the blended mid-point. Prevents a single bad extrapolation from dragging the headline.

Recency decay for secondary trades

180-day half-life (e⁻ᵈ/¹⁸⁰)

A trade from 30 days ago counts ~5× more than one from 180 days ago. Tunable; some platforms use shorter half-lives.

Tax estimate

US federal only, single filer

Uses 2024 US federal brackets, ignoring state tax, NIIT, AMT credit recovery, and any other deductions. Treat as a directional sanity check, not a tax bill.

All data from public sources. Not investment, tax, or legal advice. Not affiliated with OpenAI. Last refreshed manually — see methodology for our update cadence.