Astrology · Free tool · Progressions
Your progressed chart, computed.
Day-for-a-year symbolic projection of the natal chart. Cast for any date — secondary, solar arc, minor, or converse. Tight progressed-to-natal contacts surfaced; the inner-life chapter you’re actually in.
Secondary progressions are the modern Western inner-clock: one day after birth equals one year of life. The progressed Moon (which shifts sign every ~2.5 years) names the inner-life chapter; the progressed Sun marks identity-evolution every ~30 years. Tight contacts to natal placements are the trigger points when long-running internal patterns step outward.
For the moment-to-moment timing, see the transit forecast. For the year-shape (Hellenistic), see annual profections and the solar return.
Common questions
About secondary progressions
What are secondary progressions?
A symbolic projection of the natal chart developed in the 16th century: one day after birth equals one year of life. Day 30 of the ephemeris becomes age 30. The progressed chart slowly rotates through the natal: the progressed Moon shifts sign every ~2.5 years, the progressed Sun every ~30 years, the slower bodies barely move. Modern Western practice uses the progressed Moon's house as the primary chapter-marker for the inner life.
How do I read a progressed chart?
Three handles. The progressed Moon's sign and house tells you the inner weather of the current chapter — what your emotional life is rehearsing. The progressed Sun's sign-change (every ~30 years) marks a major identity-evolution. Tight progressed-to-natal aspects (within 1°-2°) are trigger moments — when a long-running internal pattern takes outward shape. Pair with transits to time when something will land.
What's the difference between secondary, solar arc, minor, and converse?
Secondary: day-for-a-year, the standard. Solar arc: every body moves at the rate of the Sun's daily motion (~1°/year), so the whole chart shifts at the same rate — favored by Hellenistic and Vedic practitioners. Minor: progresses one lunar month per year, scaled differently — gives finer texture for the inner life. Converse: runs the day-for-a-year clock backwards from birth — for ancestral / past-life threads. Default to secondary; toggle the others when a working chart asks for them.
Why are the orbs so tight?
Progressed motion is glacial — the progressed Moon moves about 13° per year, every other body moves a fraction of a degree per year. By the time a progressed aspect builds to within 1°, it's been in the user's life for years; when it hits exact, something fires. Looser orbs (5°+) would surface aspects that are a decade away from perfection — useful for theory, noisy for practice. We use 1.5° for major aspects and 1.0° for sextile, the standard for predictive progressions.
How accurate is this?
Arcsecond-grade. The engine uses VSOP87D for the planets and a truncated ELP2000 lunar model with deltaT correction — the same ephemerides as the free Birth Chart and Sky Map tools. Houses default to whole-sign for the overlay (cleaner for predictive work than Placidus, especially at high latitudes).
Why is this free?
Computing a progressed chart is mechanical — every working astrologer needs one and most consumer apps charge for it. The interpretation is where Calibrate adds value, by telling you which timing technique actually scores best for your life so you know which set of aspects to take seriously.
Computation
Progressed positions computed from VSOP87D (planets) + a truncated ELP2000 model (Moon) with deltaT correction. Default method is secondary (day-for-a-year). Solar arc moves every body at the Sun’s daily rate (~1°/year). Minor uses the lunation cycle as the proportion. Converse runs the clock backwards from birth. Houses overlay uses whole-sign from the natal Ascendant. Aspect orbs: 1.5° major / 1.0° sextile — tight, the standard for predictive progressions.