ERA is a personal AI astrologer. It calculates your exact natal chart, progressed chart (who you are today, not just who you were born as), and planetary life cycles to give you strategic, personalized interpretations — not generic horoscopes based only on your sun sign.

How does ERA calculate my natal chart?

ERA uses your exact date, time, and place of birth to calculate the precise position of all planets, the Ascendant, and the 12 astrological houses at the moment you were born, using high-precision astronomical ephemeris (Swiss Ephemeris).

How is ERA different from other horoscopes?

ERA doesn't use your generic sun sign. It calculates your complete natal chart, current progressed chart, and planetary cycles to answer specific questions about your real situation — work, relationships, relocations, compatibility. Every answer is based on your exact sky, not generic predictions for millions of people.

Does ERA use artificial intelligence?

Yes. ERA combines precise astrological calculations with advanced artificial intelligence to interpret your natal and progressed chart. The AI is built on a unique interpretive methodology transmitted through real practice — delivering strategic interpretations, not generic responses.

What is a progressed chart?

A progressed chart shows how your natal chart has evolved over time. It reflects who you are today, not just who you were born as. ERA bases its interpretations primarily on your current progressed chart, making every answer relevant to your present moment.

What is astrocartography?

Astrocartography shows how your astrological chart changes depending on where in the world you live. ERA can calculate how your planets and houses would reorganize if you moved to another city or country, helping you make relocation decisions based on your chart.

Can I use ERA for free?

Yes. ERA has a free plan with 5 messages per month. The Pro plan costs $9/month (or $90/year with 2 months free) and includes unlimited messages and full access to all astrological interpretation features.

Does ERA work on Android?

Yes. ERA is available as a progressive web app (PWA) at eraastrology.ai and as a native Android application. It can also be installed directly from the browser on any device.

Guides

Synastry: How to Compare Two Charts to Understand Real Compatibility

Compatibility is not about sun signs. It is about how two complete charts interact.

By ERA Astrology·March 25, 2026·2 min read

"Aries and Libra are compatible." "Taurus and Scorpio attract but clash." These are the sun-sign simplifications that dominate popular astrology. Real synastry is something completely different: it is the study of how two complete natal charts interact with each other. Where one person's planets fall in the other person's houses. What aspects form between the two charts. And — what nobody else does — how both people's progressed charts modify the current dynamic. ERA does synastry with the depth this technique deserves.

What synastry is and how it works

Synastry overlays two natal charts and analyzes the interactions. If your Venus falls in your partner's 7th house, your presence directly activates their relationship area — they feel naturally drawn to you. If your Saturn squares the other person's Sun, there is tension between your structure and their identity — it can be a challenge that generates growth or frustration depending on both people's maturity.

The aspects between planets of two people are the heart of synastry. Conjunctions create fusion. Trines create flow. Squares create productive friction. Oppositions create polarized attraction. There are no "bad" aspects in synastry — only aspects that require more awareness.

Serious synastry does not limit itself to saying "compatible" or "incompatible." It shows exactly where the relationship flows, where there is friction, and what needs conscious work.

What ERA does differently in synastry

Most compatibility apps compare sun signs and give you a percentage. That is not synastry — it is a game. ERA compares the complete charts of two people: all planets, all houses, all aspects.

But ERA goes a step further. It analyzes how both people's progressed charts interact at this moment. Because a couple that was highly compatible five years ago may be experiencing a different phase now — if one person's progressed Moon changed signs and no longer aspects the other's Venus, the emotional dynamic has changed.

ERA shows you compatibility as it is now, not as it was at birth. That is real synastry — dynamic, precise, and anchored in the present.

What makes ERA different

ERA does synastry with complete and progressed charts. It shows you current compatibility, not a percentage based on sun signs.

Your chart isn't generic. Your reading shouldn't be either.

ERA calculates your progressed chart and tells you exactly how these transits affect you.

Talk to ERA about your chart

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Astrocartography: What Each Planetary Line Means on Your Map