Does the hour count account for daylight saving time?
No. The tool multiplies the total number of days by 24 and does not try to reconstruct daylight-saving changes for any country. In places that observe that change, the real clock can have a 23-hour or a 25-hour day twice a year, which this calculation does not reproduce.
Why not use the "how many days have I lived" page instead of this one?
Because a search for hours wants the number already converted, without an extra step. This page opens the calculator with the same civil-day calculation, but prioritizes the hour and minute totals in the primary answer instead of the day and week totals.
Can the minute total become imprecise at very large numbers?
No, it does not lose precision from rounding: minutes are a plain whole number (days times 24 times 60), with no decimal places involved. The only approximation anywhere in this calculator is the month total, which uses an average days-per-month figure and does not affect the hour or minute count.