Hours ago: 1, 2, 3, 8, 12, and 24
What the common hour offsets actually mean, which searches they match, and which page to open for shift, sleep, and daily lookbacks.
Hours ago
The searches people actually type
Most hour-offset traffic is not “what time was it 11 hours ago”. It is 1 hour ago, 2 hours ago, 3 hours ago, 8 hours ago (a shift or a sleep), 12 hours ago (the other half of the day), and 24 hours ago (this time yesterday).
Each of those has its own page on this site, with the live clock and a UTC comparison. The hours-ago hub lists them in one place so you can click instead of typing.
1–3 hours
These are near-term reconstructions: a meeting that ended, a build, a commute. They often cross noon or midnight, which is why people stop doing them in their head. One hour ago is the default; two and three hours cover “late morning / early afternoon” gaps.
8 and 12 hours
Eight hours is a work block. Twelve hours is a watch. If you ask at 21:00, 8 hours ago is 13:00 and 12 hours ago is 09:00. Neither is “yesterday” unless you ask after midnight. Read the date on the result, not only the hour.
24 hours
Twenty-four hours ago is the same clock time on the previous date. Use it when a job runs once per day and you need the previous run’s timestamp. For “yesterday morning” as a vague phrase, it is the wrong tool unless you are asking in the morning.
Questions
Why is 7 hours ago on this site at all?
Some regions and some on-call rotations think in 7-hour blocks, and some users bookmark whatever they typed last. The more common lookups are 1, 2, 3, 8, 12, and 24 hours.