In astronomy, the meridian is an imaginary line running north to south through the sky, passing directly overhead. When a planet crosses it, that planet is at its highest point — its moment of maximum visibility and influence. In navigation, your meridian is your exact line of longitude: your precise position on Earth. To know your meridian is to know exactly where you are.

In astrology, the meridian divides the chart into what is visible above the horizon and what operates beneath it. Most of what actually governs timing — the planetary positions, the personal arcs, the numerical cycles — runs below the surface of the calendar most people use. It's not hidden because it's secret. It's hidden because the system we navigate daily, the Gregorian calendar, was built for administration, not for reading these conditions.

The Hidden Meridian is the real position beneath the official one. This app makes it readable.

A structured timing system. It overlays natural cycles — planetary, seasonal, and numerical — onto daily life. Not to predict what will happen, but to describe what conditions are currently available and what they're asking for.

Most decisions feel harder than they need to because they're made without reference to timing. This isn't about fate or belief. It's about knowing whether the moment supports building or consolidating, pushing or resting, starting or finishing — and acting accordingly.

No mysticism, no predictions. Just position.

Cyclical timing has been practiced continuously for thousands of years — by Babylonian astronomers, Greek philosophers, Renaissance scholars, and the courts of every major civilisation. It was not a fringe belief. It was operating infrastructure for decision-making at the highest levels of power.

At some point it got reclassified. The rise of mechanistic science treated anything unquantifiable as superstition. Then mass-market popularisation finished the job — replacing practical content with vague personality typology and horoscope columns. What remained in public view was a hollowed-out shell.

The practical layer never disappeared. Cyclical timing — knowing where you are in long arcs, reading when conditions favour certain kinds of action — is still actively used by people operating at senior levels of finance, politics, and strategy. It's just not discussed openly, because the public version of the same knowledge has been so thoroughly discredited by its own popularisation. This app is the practical version.

The Gregorian calendar was introduced in 1582, not to align human life with natural cycles, but to fix the drift in the ecclesiastical calendar — specifically to keep Easter on the correct date relative to the spring equinox. It is an administrative tool. Its months are arbitrary lengths, its year begins in January for no astronomical reason, and it has no relationship to the Moon, the seasons as felt, or any cycle that governs biological or psychological rhythm.

Before it, most cultures organised time around cycles that were actually visible and felt — lunar months, solar quarters, the rhythms of planting and harvest. These weren't poetic framings. They were practical. The body responds to light cycles, the Moon affects tides and fluid systems, seasons shape energy and mood in ways that are well-documented even in contemporary research.

The result of living by an administrative calendar is a kind of chronic disorientation — acting on arbitrary dates (new year, fiscal quarters, arbitrary deadlines) while being largely unaware of where you actually are in the cycles that affect you. This app runs on the real cycles underneath the Gregorian grid.

Check Now when making a decision, starting something new, or when things feel harder than they should. The most useful practice is consistent check-ins — not to follow instructions, but to build a felt sense of where you are in each cycle. The system becomes useful when you can feel the waning Moon before you read it.

Each timescale shows a briefing — a few lines naming what is actually present right now — and a SWOT grid: what is available, what is depleted, what is building, where the friction is. Where systems agree, the signal is reinforced. Where they conflict, the tension is named in red — because the conflict itself is information.

A "Coming up" section names the next significant ingresses and arc transitions. Tap any cycle to ask a question about it directly.

A single synthesised picture of who you are across every system the app reads. The portrait at the top names the major facets — core character, emotional nature, how you meet the world, dominant element, BaZi Day Master, lunar nakshatra, Human Design type, Gene Keys life's work, and others. Below it, an evidence section opens each tradition for the underlying detail.

Each tradition is a different lens on the same position. Where they agree about you, the signal is strong. Where they disagree, the disagreement itself is information about how you actually move through different registers of life.

Every planet moves at a different speed and produces a different timescale of influence. Each planet has a phase (New / Waxing / Full / Waning) describing the direction of its current cycle, and a sign describing the qualitative character of its expression. The combination produces the specific read.

Two short-term overlays modify these readings. Retrograde — when a planet appears to move backward (Mercury 3–4×/year, Venus & Mars less often, Jupiter & Saturn for months at a time) — asks you to revise, re-read, and re-examine in that planet's domain before committing. Void of Course Moon — the hours after the Moon makes its last major aspect in a sign before changing — is the classical advice not to start anything that needs to stick. Both are surfaced explicitly in the Now tab when active.

Jupiter returns to its birth position every 12 years. Saturn every 30. Uranus every 84. These returns mark cycle boundaries personal to you — not shared with everyone born in your era. Your position within these arcs describes what kind of effort the longer-term rhythm currently supports or resists.

These require your birth year to compute. The more specific the birth date, the more accurate the personal month and day numerology layers become. Birth time, when known, sharpens the Ascendant and the Moon's exact degree — both of which move quickly enough that an unknown birth time leaves them approximate.

Western astrology is one lens. Other traditions read the same moment through different geometries — sidereal stars, elemental cycles, archetypal grids, lunar-based calendars. Each adds something the others cannot see on their own. The You tab shows what each one reads about you; the Now tab folds them into the current briefing where relevant.

A parallel personal layer running on Pythagorean reduction. Your birth date produces a Personal Year (resets each January), Personal Month (changes monthly), and Personal Day (changes daily). Each number 1–9 describes a natural orientation for that period — initiation, consolidation, completion, and so on.

Where numerology aligns with the planetary signals, the path is reinforced. Where it conflicts, the tension is named — because the conflict itself is information. A Personal Year 9 (completion) inside a Jupiter Build phase means the arc supports expansion, but your personal rhythm is asking you to finish before you add more.

No single tradition has a complete view. Western astrology reads the geometry of the sky, Vedic reads the fixed stars behind it, BaZi reads elemental cycles, Human Design reads the bodygraph, the calendar systems read time itself in different units. Each was developed independently — often without contact — and yet they describe overlapping territory.

When several traditions agree about a moment or a person, the signal is strong: convergent evidence across independent methods. When they disagree, the disagreement is also information — it points to a place where the registers of your life genuinely diverge. The app keeps every lens visible rather than picking one and calling it the answer.

A free-form question interface. Ask about a decision you're weighing, a tension you can't name yet, or what any part of your reading means in practice. Your full portrait — every system the app has computed for you — is sent as context with the question, so the answer is grounded in your specific position rather than generic.

Ask uses the Anthropic API. Your question and the relevant portrait context are sent to Anthropic's servers; nothing else leaves your device.

A planning surface. Most timing apps tell you what cycles are active right now — Calendar lets you ask the reverse: given what I'm trying to do, when does the sky support it? Pick one of the six pre-defined endeavours (Launch, Sign, Hard talk, Start, Travel, Rest) and the visible month colour-codes from best to poor. The colour comes from a small electional rubric per endeavour — moon phase, moon sign element and modality, retrograde flags, personal-day numerology, day of week.

If your endeavour doesn't fit any of the six, type it in the input. The phrase is sent to Anthropic, which returns a custom rubric in the same shape as the pre-defined ones — same constrained vocabulary, same scoring math. The calendar then recolours using your phrase's rubric. Submitting a freeform phrase clears any selected chip; selecting a chip clears the freeform.

Tap any day to open a drawer with the full breakdown — the score, every rule that contributed to it (with its delta), the moon's phase and sign for that day, retrograde flags, slow-planet transits to your natal points within one degree, and your personal-day number. Below the grid, the Best Windows section ranks the top runs of consecutive good-or-better days in the next ninety days; tap a row to jump straight to that month's peak.

The rubrics here are deliberately simple — closer to a classical electional checklist than a full electional engine. Treat them as a first-pass filter, not the last word. The drawer always shows you the reasoning so you can disagree with any rule.

No event prediction. No compatibility analysis. No fixed personality typing. No fatalism — positions describe conditions, not outcomes. The system tells you what the environment is doing. What you do with that is yours.

All computation runs locally in your browser. Birth data is stored only on your device. The single exception is the Ask tab, which sends your question and portrait context to Anthropic to generate the response.

Operator: The Hidden Meridian (early-access project, not yet a registered business entity). Last updated: 2026-05-07. This app is in private early access; a registered legal entity, contact details, and full GDPR identification will be added before public launch.

What we collect. When you complete the intro: name (optional), date of birth, time of birth (optional), place of birth (optional). When you use the app: bookmarks you save. Ask history is in-memory only and is wiped on refresh.

Where this data lives. On your device only. All data is stored in your browser's localStorage. We do not have a server-side database. We do not have user accounts.

Where data is sent during use.

Anthropic (USA) — your birth data is included in synthesis requests to Claude. When you use the Ask tab, your first name, your question, and your portrait context are also included. Anthropic retains API logs for up to 30 days for trust and safety; they do not train on API data by default. See anthropic.com/privacy.

Cloudflare (USA / global edge) — requests to Anthropic transit through a Cloudflare Worker that holds the API key. Cloudflare logs request metadata (IP, timestamps, headers) for routing and abuse prevention. See cloudflare.com/privacypolicy.

OpenStreetMap / Nominatim (UK/EU) — when you type your birth city, the place name is sent for coordinate lookup. See Nominatim privacy.

No analytics or tracking is currently enabled.

Legal basis (GDPR). Consent. You provide birth data voluntarily during the intro. You can withdraw consent at any time by tapping Delete my data below.

Your rights. Access — your data lives on your device; you can inspect your browser's localStorage to see what's stored. Erasure — tap the button below; this wipes all stored data on your device. Rectification — re-do the intro to correct any wrong birth data. Withdraw consent — delete your data as above.

For data Anthropic and Nominatim hold, contact them directly per their policies.

EU residents can complain to their national data protection authority. In Lithuania: VDAI.

Children. This app is not directed at children under 16. Don't enter data about a child without their guardian's involvement.

Changes. We may update this policy. The "Last updated" date will change. Substantial changes will be flagged on next app open.

Contact. This is a private early-access version. If a friend gave you this link, contact them. A public contact channel will be added before public launch.

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