Why your birth time matters (and what to do if you don't know it)
Updated September 25, 2026
Your birth time determines three things: your rising sign, your houses and your Midheaven — the parts of a chart most tied to work and career. It also pins down your Moon sign, since the Moon moves about 13° a day. Without a time you still get accurate planet signs and a useful daily brief; you just won't get houses or rising sign.
Where to find it
- A long-form birth certificate (U.S. states often include time)
- Hospital records or baby books
- Asking family members
What changes with a birth time
| Without time | With time |
|---|---|
| Sun and planet signs | + Rising sign |
| Moon sign (approximate) | Exact Moon sign |
| No houses | Whole sign houses |
| No Midheaven | Midheaven |
How Tutelox handles unknown times
We calculate at local noon, hide houses and the rising sign, and mark the Moon "approximate."
Questions
- How accurate does the time need to be?
- Within about 15 minutes is usually fine; near a sign boundary, closer matters.
- Does time zone matter?
- Yes. We use historical time zones, including past daylight saving rules.
- Can I add my birth time later?
- Yes, in Settings. Your chart recalculates immediately.
- Is my birth data private?
- It's stored securely, never shared with advertisers, and deleted when you delete your account.
Get your personal work brief
Based on your full chart and today’s schedule, delivered at 5 AM.
See my briefBy the Tutelox editorial team. Positions come from NASA JPL ephemeris calculations; the writing is AI-assisted and reviewed by people. How we make this.
For entertainment and self-reflection. Not professional advice.