Kpler's three Hormuz crossings do not prove outbound oil volume fell 73%

By Cumulant Research

The most arresting Hormuz number published on July 17 was three. That was the number of commodity vessels Kpler recorded crossing on July 16, compared with 11 vessels the previous day, according to [Reuters](https://www.timesofisrael.com/straitstraitA strait is a narrow waterway connecting two larger bodies of water.-of-hormuz-transits-drop-as-us-and-iran-escalate-attacks-across-gulf/). The difference is eight vessels. Eight divided by 11 is about 73%.

That calculation is correct, but it answers only a vessel-count question. It does not answer how many barrels of crude oilcrude oilCrude oil is petroleum in its unrefined form before it is processed into fuels and other products. or refined products moved outward. Counting ships without their cargo quantities is like counting delivery vehicles without knowing whether each is an empty van or a full tractor-trailer.

A defensible volume estimate needs, at minimum, each vessel's direction, cargo type, cargo quantity, crossing time and any later correction to its voyage record. None of the public pages reviewed here supplies that complete ledger for every Kpler crossing on both days. The [July 17 Reuters report](https://www.timesofisrael.com/strait-of-hormuz-transits-drop-as-us-and-iran-escalate-attacks-across-gulf/) gives a total of three for July 16 but names only two outbound vessels and does not state their cargo quantities.

The absence of a public ledger does not prove that oil volume stayed level. It also does not prove that volume fell. It means the size of the change cannot be recovered reliably from the published crossing total.

A ship count measures movements. A barrel estimate requires cargo quantities, directions, crossing times and later revisions.

The [currently accessible Reuters page dated July 16](https://www.investing.com/news/commodities-news/fewer-vessels-travel-through-hormuz-as-us-iran-continue-strikes-4794715) says Kpler counted nine crossings on July 15: five vessels entered the Gulf and four exited. The [July 17 Reuters report](https://www.timesofisrael.com/strait-of-hormuz-transits-drop-as-us-and-iran-escalate-attacks-across-gulf/) gives 11 for the same day.

Neither public article explains whether the difference resulted from a later cutoff, a newly reconstructed voyage or a changed filter. Calling one figure wrong would therefore go beyond the evidence. The safe statement is that the published total changed.

The choice of starting figure matters. The move from nine to three is a decline of six vessels, or about 67%. The move from 11 to three is a decline of eight vessels, or about 73%. Neither percentage becomes a barrelbarrelA barrel is the standard oil-volume unit used in energy markets. estimate merely because the arithmetic is precise.

[Argus reported](https://www.argusmedia.com/en/news-and-insights/latest-market-news/2853183-attacks-push-ships-to-iran-linked-hormuz-route) 29 Windward-tracked commercial movements on July 15, consisting of 18 inboundinboundInbound means moving into the Persian Gulf through the Strait of Hormuz. and 11 outbound movements. [AP reported](https://apnews.com/article/iran-us-hormuz-strait-war-july-17-2026-2ad0cfe592eb258cb15a9eb04411d58a) eight MarineTraffic crossings on July 16. Reuters reported three Kpler commodity vessels on July 16.

Those totals differ in date, stated vessel category, direction detail and detection description. Comparing them directly would be like comparing the number of freight trucks on a road with the number of all commercial vehicles. A broader category can produce a larger count without contradicting a narrower one.

Kpler and MarineTraffic also should not be presented as fully independent corporate sources. [Kpler announced](https://www.kpler.com/blog/kpler-acquires-marinetraffic-and-fleetmon-for-maritime-sector-expansion) that it acquired MarineTraffic in 2023. Their products can still apply different filters and methods, but common ownership means apparent agreement is not the same as corroboration from an unrelated company.

AISAISThe Automatic Identification System is a radio system through which a ship broadcasts identifying, location and movement information. is a ship's radio broadcast of identity, position and movement. The [International Maritime Organization](https://www.imo.org/en/ourwork/security/pages/faq.aspx) says fitted ships generally must keep AIS operating, while its guidance allows a master to switch it off where an attack by pirates or terrorists is imminent. A blank public tracking screen therefore does not prove that no vessel crossed.

Kpler says its system goes beyond uninterrupted AIS tracks. In a [July 6 company methodology example](https://www.kpler.com/fr/blog/tracking-recent-aluminum-disruptions-with-kpler), it said analysts manually validate Hormuz crossings affected by AIS shutdowns, position-signal interference or spoofing. The example concerned alumina cargoes, not the July 16 oil count.

The company page establishes Kpler's claimed capability, not which reconstructed voyages were included in Reuters' three-vessel figure. Adding every vessel that later reappeared outside the strait could double-count a crossing already present in Kpler's total.

The [U.S. Energy Information Administration](https://www.eia.gov/outlooks/steo/report/energysecurity/article.php) describes a similar problem in its own work. It supplements AIS-based data with origin, destination and route information, estimates crossing dates for otherwise unidentified cargoes and warns that 2026 Hormuz tracking data are being revised frequently.

Reuters identified Miraan, a product tankerproduct tankerA product tanker normally carries processed petroleum fuels rather than unrefined crude oil. carrying fuel oilfuel oilFuel oil is a heavy petroleum product used in ships, industrial equipment and some power plants., and Norita, a small vessel carrying LPGLPGLiquefied petroleum gas is mainly propane and butane stored as a liquid under pressure., as having exited through the Iran-operated route on July 16. Both then stopped in the Gulf of Oman, according to [Kpler data reported by Reuters](https://www.timesofisrael.com/strait-of-hormuz-transits-drop-as-us-and-iran-escalate-attacks-across-gulf/). The article does not publish their cargo volumes or identify the third counted vessel's cargo and direction.

Crossing the strait proves movement through the counting boundary. It does not by itself show that a cargo reached a buyer, avoided later delay or belonged inside the requested category of outbound crude oil and refined petroleum products.

The same Reuters report says two VLCCs appeared on AIS outside the strait on July 16 carrying 2 million barrels of crude each. Kpler assigned their crossings to July 13, while S&P Global Energy assigned them to July 14. Those ships demonstrate why later observation and crossing-date assignment matter. They are not evidence of four million additional barrels crossing on July 16.

• Identify every counted vessel.
• Separate inbound ships from outbound ships.
• Separate empty vessels from laden vessels.
• Record crude oil, refined products, LPG and non-oil cargoes separately.
• Use the actual cargo quantity rather than a standard capacity assumption.
• Apply one documented daily boundary and preserve later corrections.

Reuters said renewed fighting and the traffic slowdown were pushing energy prices higher. That is evidence of a market reactionmarket reactionA market reaction is a price movement caused by traders changing expectations about risk, supply or demand.: traders were changing prices in response to expected supply risk. It is not a direct measurement of how many barrels left the Gulf on July 16.

The distinction matters because expectations can move before the physical effect is known. Conversely, oil already stored outside the Gulf, pipeline exports and later deliveries can soften the immediate economic effecteconomic effectAn economic effect is a measured change in physical supply, production, costs or consumption rather than a change in expectations alone. even when ship traffic falls. Those mechanisms require separate evidence and should not be inferred from the Kpler crossing ratio.

For scale, the [EIA estimated](https://www.eia.gov/outlooks/steo/report/energysecurity/article.php) that total oil flows through Hormuz averaged 14.6 million barrels per daymillion barrels per dayMillion barrels per day is an average flow rate showing how many millions of barrels move during a typical day in the measured period. in the first quarter of 2026. That is a quarterly estimate built from tankertankerA tanker is a ship built to carry liquids or gases in large storage tanks. tracking and additional analysis. It is not a substitute for a daily July cargo ledgercargo ledgerA cargo ledger is a vessel-by-vessel record of ship identity, direction, crossing time, cargo type and cargo quantity., and the EIA explicitly says its 2026 Hormuz estimates are frequently revised.

The [EIA's July 15 review](https://www.eia.gov/todayinenergy/detail.php?id=67865) links second-quarter Hormuz disruptions to higher and more volatile crude prices, alternative sourcing and changes in U.S. exports and refinery activity. Those are measured economic effects assembled from several datasets. They cannot be assigned to the July 16 crossing count alone.

What can be said is narrower and still consequential: Reuters published a steep decline in Kpler's daily vessel count as military risk increased and the United States resumed its blockade of Iranian ports. The comparison is provisional because the July 15 total differed between reports, and it is not a volume measure because the public record lacks complete direction and cargo data.

A later vessel-level release could show that outbound oil fell sharply. It could also produce a smaller or larger percentage than the ship count. Until that record is available, turning three crossings into a barrel-flow decline would replace missing evidence with an assumption.