Strait of Hormuz Closure Day Count Explained (Day 237 = What?)
Explainer · Published 23 Oct 2026 · Convention fixed in the methodology; the day number in the status line below updates daily
On 23 October 2026 the Strait of Hormuz is on Day 237 of its closure, counted from 28 February 2026 as Day 0. That is the day the US and Israel opened strikes on Iran and the IRGC began warning merchant ships off by radio; 13 ships transited on 22 October against a pre-crisis norm of about 88 a day. Other trackers show Day 238, Day 235 or “7 months, 3 weeks” for the same morning. None of them is wrong. They start the clock on different days, and this page explains each one.
Status as of 13 Nov 2026: Closed, Day 258. 10 transits on 12 Nov 2026 vs ~88/day pre-crisis. Brent $95.18. Full SITREP →What is “Day 237” counting from?
This site counts days elapsed since 28 February 2026, which is Day 0. 1 March is Day 1, 30 September is Day 214 and 23 October is Day 237. The count runs in UTC, uses calendar days rather than 24-hour periods, and never pauses: the April ceasefire, the brief rise to around 20 transits a day in late June, and the resumed US blockade in July all happened inside one continuous count, because at no point did commercial traffic return to normal.
Why 28 February rather than the IRGC’s formal announcement? Because that is when ships stopped moving. Lloyd’s List Intelligence counted 72 cargo-carrying vessels through the strait on Saturday 28 February, down 38% on the day, and only 8 by 18:00 UTC on Sunday 1 March. Wikipedia dates the crisis to the same day and notes the strait was “largely blocked” from 28 February even though the IRGC only confirmed a closure on 2 March and Tehran declared it on 4 March. The day the market stopped is a better anchor than the day a spokesman spoke.
Why do trackers show different day numbers?
There are three choices hidden inside any day count: which date is the anchor, whether that date is Day 0 or Day 1, and whether the count is a number of days at all. Each live tracker makes those choices slightly differently.
| Tracker | Anchor date | Anchor = Day | Shown on 23 Oct 2026 | Note |
|---|---|---|---|---|
| The Strait of Hormuz (this site) | 28 Feb 2026 | Day 0 | Day 237 | Days elapsed; continuous, UTC. Fixed in the methodology. |
| straits.live | 28 Feb 2026 (implied) | Day 0 | Day 237 | “Day 237 since the closure began”; its brief does not state the anchor, but the number matches a 28 Feb = Day 0 count. |
| hormuz.now | 28 Feb 2026 | Day 1 | Day 238 | Ordinal count: the first day of the crisis is “day 1”. Its own note says trackers anchored to the IRGC confirmation show about two fewer. |
| Trackers anchored to the IRGC confirmation | 2 Mar 2026 | Day 0 or 1 | Day 235 or 236 | Uses the first official Iranian statement rather than the traffic collapse. |
| Wikipedia | 28 Feb 2026 | n/a | “months and weeks” (read “6 months and 3 weeks” at our last check) | Infobox duration, not a daily counter; it is edited by hand and can lag the calendar by weeks. |
So a one-day gap between two trackers is almost always a Day 0 versus Day 1 choice, a two-day gap is almost always 28 February versus 2 March, and a three-day gap is both at once. If you are quoting a day number in a report, say which convention you used; if you are comparing two trackers, subtract the convention before you conclude one of them is late.
Does the count pause when ships get through?
No. The counter measures time since the closure began, not time at zero transits. Ships have moved through the strait on every day of the count: Windward logged between 6 and 18 transits a day through October, and Kpler tracked 895 crossings between 1 March and 19 May, 94% of them outside the IMO lane. What has not happened is a return to anything like the pre-crisis norm. The site’s status rubric, set out in the methodology, calls the strait “Closed” while transits run below 25% of the ~88/day baseline, “Restricted” between 25% and 75%, and “Open” above 75%. The day count would keep running through a “Restricted” phase too; it stops only when the status reaches “Open” and the dataset records a reopening date.
The one earlier near-miss was June. Al Jazeera’s reconstruction of the summer, drawing on Kpler and Lloyd’s List, puts the daily average at about 20 ships after the 17 June interim agreement before it fell back to about 5 when the US resumed its blockade of Iranian ports on 14 July (Al Jazeera, 27 Aug 2026). Twenty a day is 23% of baseline, below the “Restricted” line, so even on this site’s rubric the clock never stopped.
Ships or oil: which closure is the day count about?
The day count tracks vessels, not barrels, and the two have diverged sharply. Before the war the strait carried about 20 million barrels a day of crude and products, around 20% of world petroleum liquids consumption and more than a quarter of seaborne oil trade (EIA, June 2025). In October 2026, Vortexa data published by Windward show crude outflow of 10.57 million barrels on 20 October, about 62% of the pre-war ~17.1 million barrels of crude, almost all of it loaded in the UAE and moved by a US-overseen night shuttle that runs with transponders off (AP via Fast Company, 22 Oct 2026). CENTCOM says 95% of vessels that attempt the passage get through (Al Jazeera, 22 Oct 2026).
All of those statements can be true at the same time as “Day 237, 13 transits”. A handful of very large tankers can carry a lot of oil; the ~75 ships a day that are not sailing are mostly container ships, bulk carriers, product tankers and gas carriers whose cargo has no shuttle. The day count measures how long the strait has been closed to that normal commercial traffic. The oil figure measures how much of one commodity is being pushed through regardless. The SITREP reports both every day precisely so that neither can be mistaken for the other.
How to cite the day count
Write the date and the convention together: “Day 237 (28 Feb 2026 = Day 0), 23 Oct 2026”. Every SITREP title carries the day number, so the archive doubles as a lookup table, and the daily dataset has a day_of_closure column alongside the date so that anyone reusing the numbers can re-base them to another convention with a single subtraction. The SITREPs of 29 September to 8 October 2026 were originally numbered one day low and were corrected on 23 October; each carries a dated correction note, and the change is logged in the methodology’s revision log.
Frequently asked questions
What day of the Strait of Hormuz closure is it today?
On 23 October 2026 it is Day 237, counted from 28 February 2026 as Day 0. The status line at the top of this page, and every daily SITREP, carries the current number.
Why does hormuz.now say Day 238 when this site says Day 237?
Both anchor to 28 February 2026. hormuz.now calls that first day “day 1” (an ordinal count); this site calls it Day 0 (days elapsed). The two will always differ by exactly one. Trackers that anchor to the IRGC’s 2 March confirmation run two days lower again.
Has the strait been closed for the whole count, or did it reopen in between?
Commercial traffic never returned to normal. The highest sustained level was about 20 ships a day after the 17 June interim agreement, roughly 23% of the ~88/day baseline, and it fell back to single digits when the US blockade resumed on 14 July. The counter does not pause for partial reopenings.