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Learn astrology
A birth chart is built from a handful of moving parts: the signs describe styles of expression, the planets describe functions, the houses describe areas of life, and the aspects describe how it all connects. Understand those four ideas and you can read any chart.
Start with the building blocks below, then see how charts are calculated — and try one of your own.
- The 12 zodiac signsElement, modality and ruling planet for each sign, and how your Sun sign fits the bigger picture.
- The planetsWhat the Sun, Moon and planets represent, and the role each plays in a chart.
- The 12 housesThe life areas of the chart, and why they depend on an accurate birth time.
- AspectsThe angles between planets — conjunction, sextile, square, trine and opposition.
- Planet-in-sign placementsWhat specific placements mean, such as Moon in Scorpio or Sun in Gemini.
- Rising signsThe Ascendant through the twelve signs — first impression, and why it needs a birth time.
- Synastry aspectsWhat a cross-chart contact means, then compare both charts to see if you have it.
- Sun-sign compatibility guidesStarting-point pair explainers. Sun signs are one layer — the calculator compares two full charts.
- How to read a birth chartThe four building blocks and a simple order to interpret any chart.
- Yearly Forecast & Solar ReturnAnnual transits and the Solar Return for a selected year, from your natal chart — not a sun-sign horoscope.
- How Solar Returns WorkThe chart for the moment the Sun returns to its natal longitude — and how it differs from transits.
- Astrology Transits ExplainedMoving planets contacting a natal chart: aspects, exact hits, and the year-ahead scan versus Today's Sky.
- Why your birth time mattersWhat the rising sign, houses and angles depend on — and how precise the time needs to be.
- Birth chart without a birth timeWhat stays accurate, what gets left out, and how to get a chart anyway.
- Birth chart vs natal chartTwo names for the same chart — and the chart types that really do differ.
- How birth charts are calculatedWhy date, time and location matter, and what happens without a birth time.
- MethodologyThe calculation pipeline from birth input to a finished chart.
- Data sourcesThe ephemeris, timezone and place data behind every chart.
Ready to read your own chart?
Put the building blocks together with your real placements.
Calculate your birth chart