Secondary Progressions

Secondary Progressions Calculator

Astrolium's free secondary progressions calculator returns your progressed chart for any year: day-for-a-year math on the Swiss Ephemeris, under 30 seconds.

Progression Data
Calculate your inner evolution (1 day = 1 year).

What is Secondary Progressions?

The Astrolium secondary progressions calculator returns your progressed chart for any year between 1900 and 2100. Secondary progressions are the day-for-a-year technique: the chart 30 days after your birth becomes your chart at age 30. The progressed chart you see here is built on that method. Math runs on the Swiss Ephemeris in under 30 seconds. No login, no email, no upload.

The wheel shows all 10 planets, the progressed angles, and the progressed Moon's current house. Most working astrologers use secondary progressions to track slow inner change while transits handle outer events.

The full reading sits inside the progressions feature, where secondary progressions and solar arc directions stack against transits on one scrubber. For the interpretive framework, read the secondary progressions guide. For the sibling annual technique, see the solar return chart calculator. For the $29 per month Pro tier, see pricing.

What you get

The Astrolium progressed chart calculator returns the full secondary progressed wheel for any year: all 10 planets and the angles, plus the progressed Moon's current house, the next house ingress date, and any progressed-to-natal aspects within a 1° orb. Inputs are birth date, time, and place plus the target year; the tool advances each planetary position by one ephemeris day for every year of life (so 30 years of life equals the chart 30 days after birth), then renders the resulting wheel, the natal-to-progressed cross-aspects, the progressed Sun's slow march at roughly 1° per year, and the progressed Moon's faster 27.5-year cycle around the zodiac. Placidus de Tito systematised the technique in the 17th century; the math has not changed since. Math runs on Swiss Ephemeris, accurate to under 1 arc second; render time is under 300 ms. Free, no account required.

Secondary progressions are the day-for-a-year technique. Take the ephemeris position from 30 days after birth — that's your chart at age 30. Each year of life advances the planetary positions by one day. The progressed Sun moves about 1 degree per year. The progressed Moon moves about 13 degrees per year, completing one full cycle through the zodiac in roughly 27.5 years.

Placidus de Tito systematized the technique in the 17th century. The math has not changed since. What's changed is the rendering time: a manual progressed chart used to take an experienced astrologer 20 minutes with an ephemeris and a sheet of graph paper. Astrolium produces it in 300 ms. For the full interpretive method, read the secondary progressions guide.

The three layers the calculator returns

The progressed wheel

The full chart cast for the day that corresponds to your target year. All 10 planets, both luminaries, the Ascendant and Midheaven. The wheel looks like a natal chart because it is one, just at a different epoch. The differences from your natal chart are the timing.

The progressed Moon's house

The single most useful piece of information in the technique. The progressed Moon moves through one whole-sign house every 2.5 years. Each ingress flips the inner chapter: what you care about, the texture of the daily mood, the emotional question of the season. Astrolium flags the current house and the next ingress date directly on the chart.

Progressed-to-natal aspects

When a progressed planet forms an exact aspect to a natal point, the timing surfaces. A progressed Sun crossing a natal Saturn at age 33. A progressed Venus opposing natal Pluto at age 41. These contacts mark the years when the slow inner clock crosses one of your natal structural points. Astrolium computes them within a 1 degree orb. Combine this read with the profections calculator to see which natal planet is time-lord of the year the progression perfects.

How the calculator works

Drop your birth data (date, time, place) plus the target year. The math runs in your browser on the Swiss Ephemeris, the same library Solar Fire and Astro Gold use under the hood. Absolute positions match to the arc-second across the full 1900 to 2100 range.

Whole-sign houses are the historical convention for progressed-Moon house tracking, the system most working astrologers use for this technique. Astrolium supports 6 systems (Placidus, Whole Sign, Porphyry, Equal, Koch, Regiomontanus) switchable from the dropdown without re-entering birth data.

Nothing is stored. Nothing is emailed. We don't know who you are.

After the calculator

A single progressed chart is a snapshot. The reading happens when you scrub across years and see the progressed Moon move through houses, the progressed Sun change sign, the progressed inner planets cross natal points. That requires a ribbon, not a one-off wheel.

The full progressions workspace stacks secondaries and solar arc on the same scrubber as transits: Bernadette Brady's framing of progressions-as-manifestation alongside transits-as-events, on one screen. See the progressions feature for that workspace.

For the deeper reading method (how the progressed Moon's ingresses get read, how to interpret a progressed Sun changing sign, what to do when the progressed Ascendant changes sign mid-life) see the secondary progressions guide. For practitioners running progressions across a roster, the pricing page covers the $29 per month Pro tier.

Cross-link

Run related timing techniques: profections calculator, Saturn return calculator, solar return chart calculator, Jupiter return calculator. For the predictive feature stack, see predictive timing and the progressions feature.

Related

Frequently asked questions

What is the difference between progressions and transits?
Transits track the real positions of planets in the sky right now against your natal chart: where Saturn or Jupiter actually sits today, what it's aspecting. Secondary progressions are symbolic. Each day after birth represents one year of life, so the planetary motion in the 30 days after birth maps onto the first 30 years. Transits show outer events; progressions show inner unfolding. Bernadette Brady's framing: transits as the weather, progressions as the season.
How does the progressed chart calculator work?
Astrolium applies the secondary progression formula: 1 day after birth equals 1 year of life. Your progressed chart for age 30 is your natal chart plus 30 days of planetary motion. The math runs on the Swiss Ephemeris with arc-second precision. The full progressed wheel renders in under 300 ms — all 10 planets, the angles, the progressed Moon's current house.
What does the calculator return?
The full progressed chart wheel for the year you specify: progressed Sun, progressed Moon, progressed Mercury, Venus, Mars, plus the slower planets and the angles. Astrolium also returns the current progressed Moon house, the next house ingress date (the Moon moves through one house every 2.5 years), and any progressed-to-natal aspects within a 1 degree orb.
What's the difference from solar arc?
Secondary progressions move each planet at its own day-for-a-year rate — the Moon advances roughly 13 degrees per year, Saturn barely 1 degree. Solar arc advances every body by the progressed Sun's arc, so the whole chart moves in lockstep, roughly 1 degree per year. This calculator computes secondaries; the [predictive timing feature](/features/predictive-timing) ships both methods on the same scrubber.
Do I need a birth time?
Yes, for accurate house cusps and the progressed Moon's house. The progressed planet positions don't strictly require a birth time, but the progressed Ascendant, Midheaven, and the progressed Moon's house ingress all depend on the natal time. Astrolium flags missing-time charts so you don't read a house position that isn't actually grounded.
Can I run this for clients without uploading anything?
Yes. The free calculator runs in your browser — no signup, no upload. For roster-wide progression tracking (every client's current progressed Moon house, next ingress, upcoming progressed-to-natal aspects), the $29 per month Pro tier ships the full ribbon view and dashboard.

Want this inside your client roster?

Run the calculator above for a one-off chart, or save every chart you cast to a client profile in Astrolium.