Strait of Hormuz: Depth, Width and Why 20% of the World’s Oil Passes Through

Figures current as of the EIA’s August 2026 Short-Term Energy Outlook. Flows through the strait are disrupted at the time of writing; the current situation is covered below.

The Strait of Hormuz is the sea passage between the Persian Gulf and the Gulf of Oman. Its importance comes from a combination of geography and geology: it is the only sea route out of the Persian Gulf, and the countries around that gulf hold a large share of the world’s oil exports.

The physical strait: width, narrowest point, depth

Two consequences follow directly from those numbers.

The usable channel is far narrower than the strait. A strait 21 miles across at its tightest sounds roomy, but tankers do not use the full width: traffic runs in two 2-mile lanes with a 2-mile buffer. The lanes lie mostly in Omani territorial waters and partly in Iranian waters, and are governed under the UN Convention on the Law of the Sea.

The depth is what makes it hard to close. At 60–100 metres through much of its width, the strait is deep enough for the largest crude tankers and deep enough that blocking it physically is difficult to sustain. The EIA’s own framing is that the strait “is deep enough and wide enough to handle the world’s largest crude oil tankers.”

That is why disruption here has historically taken the form of attacks on ships rather than an actual closure. The threat is to the willingness of tankers and their insurers to transit, not to the water itself.

How much oil normally moves through it

The baseline, from the EIA:

• 20 million barrels per day in 2024 — about 20% of global petroleum liquids consumption
• In the first half of 2025, 20.9 million b/d, roughly a quarter of all seaborne traded oil
• Saudi crude and condensate exports were 38% of Hormuz crude flows in 2024 (5.5 million b/d)

This is the number people mean by “the world’s most important oil chokepoint”, and it is worth being precise about it: roughly one barrel in five of global consumption, not of global production or reserves.

The 2026 disruption

The picture in 2026 is not the baseline above, and any analysis written from the 2024 figures alone is describing a situation that no longer holds.

From the EIA’s August 2026 Short-Term Energy Outlook:

• Transits through the strait are under severe constraints, which the EIA assumed would persist through August 2026, with flows increasing slowly from September.
• Regional crude oil production shut-ins averaged 5.5 million b/d in July 2026.
• Brent crude fell as low as $69 per barrel on 2 July following a US–Iran memorandum of understanding signed in June, then rose to $105 per barrel on 23 July after renewed attacks on tankers transiting the strait.
• Saudi Arabia re-routed crude away from the strait via the East-West pipeline to the port of Yanbu on the Red Sea.
• A blockade threat emerged against Saudi exports through the Bab el-Mandeb Strait — which is itself both a major chokepoint and one of the alternative routes used to avoid Hormuz.

That last point is the structurally important one. The main workaround for Hormuz runs through another chokepoint, so a threat to both at once removes the redundancy that makes the pipeline alternative meaningful.

The EIA expects most regional crude production to return to near pre-conflict averages in early 2027, with ongoing disruption of about 0.6 million b/d continuing through the end of that year.

What the alternatives can actually carry

Most volumes transiting the strait have no alternative way out of the region. Pipelines exist, but they do not typically run at full capacity.

The EIA estimates about 2.6 million b/d of Saudi and UAE pipeline capacity could be available to bypass Hormuz in a disruption.

Set that against a 20 million b/d baseline and the arithmetic is stark: the bypass covers roughly an eighth of normal flows. The pipelines are a partial relief valve, not a substitute route, and the 2026 events demonstrated the point — Saudi Arabia used the East-West line, and regional production was still shut in at 5.5 million b/d in July.

Why “close the strait” is the wrong frame

Coverage often treats closure as a binary. The geography argues otherwise:

• The strait is too deep to block physically for long.
• The lanes sit largely in Omani waters, not Iranian.
• Passage is governed by UNCLOS rather than by unilateral control.

What actually reduces flows is risk: attacks on shipping, insurance costs, and owners choosing not to transit. That is what happened in 2026, and it produced a roughly $36 swing in Brent within three weeks without the strait ever being closed.

Sources

• EIA — Short-Term Energy Outlook, August 2026 (2026 disruption, shut-in volumes, Brent prices, Saudi re-routing, recovery outlook)
• EIA — Amid regional conflict, the Strait of Hormuz remains critical oil chokepoint (June 2025: baseline volumes, pipeline bypass capacity, Saudi share)
• EIA — The Strait of Hormuz is the world’s most important oil transit chokepoint (shipping lane dimensions)
• Britannica — Strait of Hormuz (width, narrowest point, depth)

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