Astrolium's astrocartography calculator is the single-location scoring tool. Feed in birth data and one target city, and it returns a 0–100 score for that location, ratings across 14 life areas, and every planetary line in orb with its angle, distance in km, and meaning. Orb is read out to roughly 700 km on the strongest contacts. Use it for client consults where the question is "what does this specific city do to my chart," not "show me the whole world."
The technique was systematised by Jim Lewis in the 1970s; the math is older. For any longitude, you can compute which planets sit on the four chart angles (AC, DC, MC, IC) at the birth moment. Each planet draws four lines around the globe. Some cities put a client's Saturn on the Midheaven. Others land Venus on the Ascendant. The lines a person spends time near tend to express.
Three astrocartography questions show up in practice. One: where on Earth do my lines fall? That's the map. Two: of these specific cities, which works for which area? That's the search or compare. Three: a client has picked a city and wants the reading. That's this calculator. The scoring layer fits relocation prep, travel timing, and on-the-spot consultation work.
What you get
The overall score reflects how the combined planetary geometry at that location sits relative to your chart. A 72 means the location has more supportive angular contacts than difficult ones. A 38 means the reverse — Saturn or Mars are close to your angles, or there are no benefics in orb at all.
The 14 life-area ratings are more useful than the headline number for most decisions. A city can score 80 overall and still rate poorly for relationships if Venus is nowhere near an angle there. The ratings are: identity, health, finance, career, love, relationships, creativity, spirituality, home, learning, communication, travel, wealth, and power. Each runs 0–10. Sort them to find where the location genuinely helps and where it doesn't.
The nearby planetary lines show every planet within orb of the target location, the line type, the distance in kilometers, and the orb in degrees. Each line comes with a meaning drawn from the API's interpretation data. Line strength is rated very strong, strong, moderate, or weak based on orb tightness.
How to read the line types
AC (Ascendant) — The planet rises on the eastern horizon at that longitude. This is the most personal of the four lines; it affects how you present yourself and how others first see you. Venus/AC locations tend to feel socially easy; Saturn/AC feels effortful and defining.
MC (Midheaven) — The planet is at the top of the sky at that longitude. This line governs career, public reputation, and your visible achievements. Jupiter/MC cities tend to expand career opportunities. Saturn/MC is demanding but often where people do their most serious work.
DC (Descendant) — The planet sets on the western horizon. This line governs the relationship axis — partnerships, marriage, open enemies. Mars/DC locations can bring conflict or intensity in one-on-one dynamics. Venus/DC draws significant partnerships.
IC (Imum Coeli) — The planet is at the base of the sky, the fourth-house cusp. This governs home, roots, family, and private life. Moon/IC locations often feel like home immediately. Pluto/IC can bring transformation through property or family matters.
After the calculator
Astrocartography scoring reads better alongside transit timing. A city that scores well during a Jupiter transit to the Midheaven feels different once that transit ends. Over a 12 months window the geographic read shifts as transits cycle. The single-location score is one input in a longer consultation, not the verdict.
Related practitioner tools
- Astrocartography Map — visual scan of all planetary lines on one world map
- Astrocartography City Finder — search 200+ cities by life area
- Astrocartography Compare — head-to-head ranking of 2–5 cities you already picked
- Astrocartography Power Zones — top 12 line crossings and paran zones
- Relocation Chart — full relocated chart for any location
- Local Space Chart — directional lines from the birth place
For deeper interpretation, see the astrocartography hub guide. For the timing layer, pair with the transit report, profections calculator, and saturn return calculator. For the natal foundation, run the natal chart report.