Why is my sidereal sun sign different from my normal one?

Western astrology uses the tropical zodiac, which is tied to the seasons and starts at the spring equinox. Vedic astrology uses the sidereal zodiac, which is tied to the actual constellations. The two have drifted about 24 degrees apart since they were aligned, so roughly four people in five get a different sign in each. Neither is wrong; they measure different things.

What is a BaZi day master?

In Chinese BaZi, your birth is written as four pillars of two characters each, covering the year, month, day and hour. The heavenly stem of the day pillar is the day master, and it stands for you. It is one of ten: a yin or yang form of wood, fire, earth, metal or water. Everything else in the chart is read in relation to it.

Do I need my exact birth time?

No, but it unlocks about half the reading. Without a time you still get your Sun in both zodiacs, your life path, your day master and your year animal. With a time and a place you also get your rising sign, your exact Moon and birth star, your Human Design type and bodygraph, and your Gene Keys.

Is Six Mirrors free, and does it store my birth details?

It is free and needs no account. Your birth date, time and place are computed in your own browser and stay there. The only thing sent anywhere is a one-way fingerprint of the birth moment so that charts can be counted; it carries no name, no email and no way to reach you.

What does it mean when several systems agree?

The six traditions share no history and no mathematics. When two or more of them independently point at the same theme in one birth, Six Mirrors names that as a thread and shows every fact it rests on. The convergence is the finding, rather than any single system's verdict.

The ledger

How this is verified,
and what it cannot yet claim

Almost everything in this category is written by a language model and checked by nobody. This page exists so you can decide whether Six Mirrors is different without taking my word for it.

The two claims worth checking

It computes rather than generates. No part of a reading is written by a language model at the moment you ask for it. Planetary positions come from the MIT-licensed astronomy-engine library and are accurate to about an arcminute. The interpretations are a fixed set of text, written by hand and curated from six practitioner rulesets, and the same birth always produces the same reading.

The arithmetic is checked against libraries that share no code with it. There are 534 automated checks in the engine harness plus six further suites in the app, run against vectors generated by Swiss Ephemeris and lunar_python. If a change breaks a position, the build fails.

What is checked, and against what

What	Ground truth	Coverage	Result
Sun position, tropical	Swiss Ephemeris	12 dates	within 0.02°
Lahiri ayanamsa	Swiss Ephemeris SIDM_LAHIRI	12 dates, 1955 to 2010	within 0.01°
Saturn position	Swiss Ephemeris	12 dates	within 0.05°
Moon sign and nakshatra, timed	Swiss Ephemeris	4 births	exact
Ascendant, tropical and sidereal	Swiss Ephemeris houses()	4 births, incl. southern hemisphere	within 0.35°
True lunar node, osculating	Swiss Ephemeris TRUE_NODE	4 instants	within 0.25°
BaZi day pillar	lunar_python	12 dates	exact
BaZi year pillar, incl. Lichun boundary	lunar_python	boundary cases 1984 and 2003	exact
BaZi hour pillar	lunar_python	4 timed births	exact
Timezone to UT conversion	IANA via Intl, hand-checked	IST, EDT, BST, AEDT	exact
Human Design gate wheel anchor	Gate 41 at 2°00' Aquarius, published	anchor check	exact
Gene Keys, all 64 triads	genekeys.com, plus two republications	64 of 64	exact
Life path, incl. master numbers	source ruleset convention	23,856 dates vs the engine	exact
Nakshatra spans and dasha lords	derived, checked against the engine	all 27	exact

What is not verified, stated plainly

Human Design type, authority and profile have been checked end to end against only two charts. The underlying gate mathematics is verified and the wheel anchor is correct, but a proper spot-check against an established calculator across several random births has not been done yet. If you use the Design tab and find a discrepancy, that is genuinely useful and I want to hear it.

The interpretations are reflective rather than predictive. Nothing here forecasts events, and the Ask feature refuses questions about lifespan and medical matters in code rather than in copy.

The convergence ontology, meaning which themes count as the same theme across traditions, is editorial. It was curated from the six source rulesets and it is the one place where judgement rather than arithmetic decides what you see. It is version-controlled and it can be argued with.

The engine is allowed to find nothing

Measured across 1,200 randomly generated charts: 2.7% produce no convergence thread at all, 9.3% produce one, and only 24.6% produce the full five. A person shares just 1.36 of five threads with a random stranger.

That matters more than it sounds. A tool that always finds a pattern is a horoscope with better typography. One earlier rule in this engine fired on three quarters of all charts, which made it a statement broad enough that almost anyone would recognise themselves. It was measured, caught and tightened to 13.8%. When this page says several traditions agree about you, it is because they did.

Where your birth details go

Nowhere. They are typed into your browser, computed in your browser, and stored in your browser. Shared readings carry the birth moment in the URL fragment, which browsers do not transmit to servers. There is no account and no email field.

One thing does leave the page, and it should be stated rather than buried: a one-way keyed fingerprint of the birth moment, so that charts can be counted. It carries no name, no email and no way to reach you, and it is stored under a key so the list cannot be read backwards.

Read your own six