Transits & Progressions Calculator — What the Sky Is Activating in Your Chart

The three timing techniques, in plain terms

Astrology tracks change over time by comparing your fixed birth chart to moving reference points. This tool shows you the three most-used comparisons at once. Transits are the simplest: where the real planets are in the sky right now, and which of your natal planets they are currently aspecting.

Progressions are symbolic: the chart is advanced one day for every year you have lived, so your 'progressed Sun' has moved about a degree per year. Solar arc takes the amount your progressed Sun has travelled and adds that same arc to every natal point, moving the whole chart at once.

Transits move fastest and are read as weather — what is being triggered this week or month. Progressions move slowly and are read as internal development — the mood of a whole season of your life. Solar arc sits in between and is used to time when different parts of the chart come 'online'. Together they give a layered sense of what is active for you now.

How each layer is computed

Transits: we evaluate the current ecliptic longitude of every planet from sub-arcsecond astronomy (VSOP87/ELP via astronomy-engine), then aspect them to your natal placements using the same orb rules as the natal chart, and mark whether each aspect is applying (closing in) or separating (letting go) from the relative speed of the transit.

Progressions: secondary progressions advance your birth instant by one calendar day per year lived, then recompute the sky at that date. The progressed Moon, moving about a degree a day (a sign every couple of years), is the most closely followed pointer; the progressed Sun, at roughly a degree a year, marks the slow background tone.

Solar arc: we measure how far the progressed Sun has moved from your natal Sun at your current age, then add that exact arc to every natal longitude. The arc in degrees is almost numerically equal to your age, which is why it reads as a yearly 'timer'.

Every value is derived from your actual chart at calculation time — nothing is pre-written or faked.

What you see

After you enter your birth data:

• Your current transits, tightest orbs first, each naming the transiting planet, the aspect, and your natal planet and house it hits.
• An applying/separating flag and orb in degrees for each.
• Your progressed Sun and progressed Moon signs beside their natal counterparts.
• Your solar arc for this year in degrees, and the sign it is directing the chart toward.

How to read it without falling for a forecast

A transit reading is best used as a lens, not a prediction. When a slow planet like Saturn or Jupiter squares one of your personal planets, tradition says there is pressure or expansion in that planet's theme — but it describes a texture, not an event. The honest use is reflective: notice whether the described theme (say, Saturn testing your House 10 career point) matches what you are already working through, and use it as a prompt rather than a prophecy.

Progressions and solar arc reward patience. Because they move so slowly, they colour years rather than days — a progressed Moon changing sign is a soft sea-change in emotional focus that unfolds over two and a half years. Read them as the season, with transits as the weather within it.

What an output looks like

Suppose your natal Venus sits at 15° Taurus in the 2nd house, and transiting Jupiter is currently at 16° Cancer. Jupiter would not be aspecting Venus (they are 61° apart, no major aspect), but it may be squaring your natal Mercury or conjunct your natal Moon elsewhere in the chart — and those are the lines that appear in your list, each with its orb and whether it is applying.

At the same time, your progressed Sun (one day per year) will have advanced about one degree per year of age from your natal Sun, and your solar arc will equal roughly that same number of degrees. The report shows the actual figures for your own chart rather than these illustrative ones.

What we don't claim

Transits, progressions and solar arc are the most-tested-seeming part of astrology because they make time-specific statements — and they are exactly where astrology has been tested most rigorously. Research has not shown that people's lives line up with their transit timings better than chance. We present these as a symbolic clock for reflection and narrative, not as predictors of events, and nothing here is advice about health, money or relationships.

Technically: your progressed and solar-arc figures depend on an accurate birth time only through the angles; the progressed planets themselves depend mainly on your birth date. Transit orbs use standard limits, so a slightly wider or narrower orb setting on another site can list a few extra or fewer aspects.

Transits vs. your natal chart vs. the solar return

The natal chart is the fixed reference everything here is measured against — cast that first. Transits and progressions add the time dimension to it. If you want a birthday-focused snapshot instead, the solar return tool casts a chart for the Sun's return each year, which is a related but different technique (a 'chart for the year ahead' rather than a live aspect list).

Our method in one line

Transiting positions from sub-arcsecond astronomy (VSOP87/ELP via astronomy-engine); secondary progressions at one day per year; solar arc from the progressed Sun. Houses Porphyry quadrant houses (whole-sign available on every chart). Reviewed by Dr. Amara Osei, Astronomy Reviewer.