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Birth times and daylight saving

A recorded birth time must be matched to the birthplace's clock rules on that date. Mạghā supports location-based zones, named IANA zones and fixed UTC offsets. When an hour repeats, inspect both occurrences before choosing the recorded instant.

One local time · two UTC instants

Repeated New York clock time
Occurrence	Offset	Universal time
Earlier · daylight saving	UTC−04:00	05:30 UTC
Later · standard time	UTC−05:00	06:30 UTC

New York · 01:30 on 2 November 2025. The two possible instants are one hour apart.

One local time can name two different moments

In the prepared New York example, the clock reads 01:30 on 2 November 2025 twice. The earlier occurrence uses UTC−04:00 and means 05:30 UTC. The later occurrence uses UTC−05:00 and means 06:30 UTC. Both have the same local date and clock reading, but they are an hour apart.

Mạghā's birth form labels the choice “This birth time occurred twice”. The Earlier and Later choices show their offsets and UTC instants. Compare them with the original record, including any daylight saving or standard-time notation. The example illustrates the choice itself. It does not establish which occurrence belongs to a particular person's birth, and selecting an occurrence does not supply missing information in a record.

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Keep the recorded time and explain the offset separately

Start with the time written in the birth record and the place where it was recorded. Choosing the location gives the form a named time zone rather than assuming that today's offset also applied in the past. “Timezone options” also lets you name an IANA zone directly when you already know the appropriate identifier.

For a documented historical correction, choose “Fixed UTC offset” and enter the offset from UTC. The format allows hours and minutes, with optional seconds for older local offsets. Keep a note of the source you used so that another reader can follow the choice. An offset entered manually expresses your decision; it does not establish whether the historical record used local mean time, standard time or another convention.

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Check the resolved time

Enter the birth date, time and place, then check the resolved time-zone line. For a repeated hour, select the occurrence supported by the record. Mạghā flags times missing during a forward clock change rather than shifting them silently.

Note: historical IANA records can be incomplete. Check disputed times against original documents and local clock history. Whole-second offsets preserve input precision; they do not establish the accuracy of the recorded birth time.

Questions about birth times and clock changes

Should I subtract daylight saving from my birth time myself?

Enter the recorded local birth time first and check the offset resolved for its date and place. Changing the clock time manually as well as using a daylight saving offset can apply the correction twice. Use a fixed offset only when your source supports that choice, and retain the reason with your birth details.

What should I do when my birth time occurred twice?

Compare the Earlier and Later UTC times with the record's daylight saving or standard-time notation. The birth form offers both occurrences. When the record gives no way to distinguish them, the form cannot decide which one was your birth; preserve the uncertainty rather than treating a default as confirmation.

What if my written birth time never occurred on the local clock?

A forward clock change can leave an interval with no matching local time. Mạghā flags a nonexistent birth time. Check the record's date, time and place, and investigate the clock rule in force. Do not silently change the written time merely to make the form accept it.

Can I enter an old offset with seconds?

Yes. The fixed-offset field accepts hours and minutes with optional seconds. Use a documented offset for the locality and date. A precise format is useful for historical corrections, but it does not make an uncertain historical source exact.

Check your birth time in Mạghā

The real prepared New York birth-time form with Later selected: UTC−05:00, 06:30 UTC. Earlier remains listed at UTC−04:00, 05:30 UTC. — A prepared clock example, not a calculated New York chart. The walkthrough enters 2 November 2025 at 01:30 for New York, compares Earlier and Later, and stops with Later selected. It never submits the form or changes the Nila natal record.

The walkthrough enters the prepared New York clock example and stops with Later selected. The Nila Raman chart is unchanged; no New York chart is created.

Check your birth details