Measuring ship traffic in the Strait of Hormuz, and what it did to refining margins - Wherobots
Skip to content
SIGN IN
Menu
TRY WHEROBOTS
Products
Products
DiscoverSpatial data, AI models, solutions, and integrations
BuildInnovate with spatial data
AutomateProduce data products with job runs
ComputeDistinguished price-performance and scale
AI for EarthBridging AI and physical world data
See all Products
Details
PricingA flexible pricing model that fits your business needs and usage patterns
SecurityPrivacy, Compliance, and Trust
Announcements
Wherobots now available on
Planetary-scale answers, unlocked.
try now
Solutions
Column Wrappper
Solutions by Role
Data Engineering
ML for Earth Observation
Data Teams
Solutions in Practice
Use Cases
Stories
See all Solutions
Industries
Aerospace
Mobility
Communication Services
Energy & Utilities
Financial Services & Insurance
Sustainability & Agriculture
Announcement
O’Reilly Cloud Native Geospatial Analytics with Apache Sedona<br>A Hands-On Guide for Working with Large-Scale Spatial Data. Learn more.
Resources
Resources
Documentation
Community
Apache Sedona
Events
Solution Gallery
Check all Resources
Insights
BlogExplore in-depth articles, tips, and expert opinions.
What’s new?Stay updated with the latest industry insights and announcements.
Upcoming Event
Fleet Observability: How Bad Telemetry Data Sabotages Modern Fleets
Company
About Us
See our storyLearn about our history, products, and values.
PressOfficial announcements, company news, and media updates.
Careers
Open PositionsStart a new journey with us – a career here at Wherobots.
Contact
Contact UsIf you have questions, feedback, or need to report an issue, just send us a message — we’re here to help!
SIGN IN
TRY WHEROBOTS
Connect your AI coding assistants to the physical world with Wherobots MCP and CLI
Learn More
8 Mins Read
19 Aug 2026
Measuring ship traffic in the Strait of Hormuz, and what it did to refining margins
Authors
Jia Yu
Damian Wylie
Engineering
Use Cases
Engineering
Use Cases
Iran closed the Strait of Hormuz to commercial shipping on 28 February 2026. To find out what stopped moving, we counted ships in free satellite imagery, month by month, from January 2025 through August 2026. Traffic through the corridor we watched fell 95%. Tankers kept loading at Iran’s Kharg Island terminal and kept waiting at anchor off Fujairah, both at 2025 levels, which means the crude was still being pumped and the ships were still turning up. Only the route between them went quiet.
Refining margins more than doubled after the closure and have stayed there. Consumers are paying the increase at the pump. The vessel count used a near-infrared threshold rather than a trained model. Sentinel-2 imagery is free and covers the planet every five days, and the whole analysis ran as one Python job in Wherobots for about $63 of compute.
What the satellites saw
We counted vessel hulls in Sentinel-2 imagery over three areas from January 2025 to August 2026. Comparing May to July in each year, so the summer sun sits at the same angle in both:
area<br>2025<br>2026<br>change
Hormuz transit corridor<br>10.3 vessels<br>0.5<br>−95%
Fujairah anchorage, outside the strait<br>63.5<br>70.0<br>+10%
Kharg Island export terminal, inside the Gulf<br>7.3<br>9.9<br>+35%
Those figures are per satellite pass, averaged over the passes clear enough to see the whole box.
We used imagery because the usual source cannot be trusted here. Ship traffic is normally tracked through AIS, the transponder every large vessel carries. In this crisis those transponders are being switched off and falsified. Near Fujairah and Khor Fakkan, roughly 470 vessels broadcast garbled or impossible positions inside a single 24-hour window. Windward counted 146 of 167 vessels in the strait area running dark on 5 May, and IMF PortWatch warns that its own numbers understate traffic for the same reason. Optical imagery records the hull whether or not the transponder is on.
What it did to refining margins
Brent ran from $72.75 before the closure to a peak of $138.21 on 7 April, then fell back to $93.26 by mid-August. Refining margins stayed elevated.
The 3-2-1 crack spread measures what a refiner earns turning three barrels of crude into two of gasoline and one of distillate, and it is the refining share of what a fuel costs. Measured against Brent, it averaged $18.17 a barrel through 2025 and held at $18.50 in the weeks before the closure. Since then it has run at $42.72, with a peak of $68.70 on 16 July.
US retail gasoline has gone from $2.94 before the closure to a national average of $4.07 this week, up 30% year on year. Diesel costs 48% more than a year ago and jet fuel more than 70%, and higher diesel alone has cost American consumers close to $40 billion since the war started, according to Brown University’s Climate Solutions Lab.
Vessel detections per satellite pass across the three areas, with Brent crude, the 3-2-1...