lunar birthdays · inner tides

Lunar Day Compatibility: Born on the Same Tide?

The Moon completes her cycle in 29.5 days, and the day of that cycle you were born on is your lunar birthday. Two lunar birthdays show whether your inner tides rise together, take turns, or complete each other. Enter two dates — the meter reads the rest.

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Two birth dates — nothing else needed

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Calculation settings — time, place, orbs, zodiac

Dimensions in the total score

Time and city unlock the eighth dimension — Ascendant × Sun. Search fills coordinates and timezone automatically; you can still adjust UTC manually.

Two dates are enough. A city adds the Ascendant; only the city search query goes to Open-Meteo, while birth dates and results stay in your browser.

What lunar birthdays compare

Each birth date falls somewhere on the Moon's 29.5-day cycle — that position is the lunar day, from the 1st (new moon, beginnings) to the 30th (the dark, quiet close). Couples born near the same phase often share an instinctive rhythm. A half-cycle apart — about 14–15 days — one gathers while the other releases: opposites that complete a whole. A quarter apart creates a creative friction that needs scheduling more than worry.

In the result above, the lunar dimension is one of seven bars. The meter also shows the exact lunar day of each partner and how the two phases meet — same tide, complementary, or offset.

Using it kindly

Lunar-day comparison is a tradition for reflection, not a filter for people. Its best use is practical: noticing that one of you starts things on the waxing tide while the other finishes on the waning — and letting that become a division of strengths instead of an argument.

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Frequently asked questions

How is the lunar day of birth calculated?

From the Moon's phase angle at the moment of birth, computed astronomically. The 29.53-day cycle is divided into 30 lunar days; the result shows both partners' days and the angle between them.

Is an opposite lunar phase bad for a couple?

No — it is the classic 'complementary' pairing: one person's fullness meets the other's release. It asks for respect of each other's phase, not avoidance.

Where does this tradition come from?

Lunar-day lore is shared by several lunar calendars popular in Russian and European folk astrology. We present it as a mirror for reflection, with the astronomy shown transparently.