About
Astrology, calculated first.
ChartLumen exists because most AI astrology tools invent placements and call it a reading. We do it the opposite way: a deterministic open astronomy engine produces the chart, and AI explains only the placements that engine found.
What we believe
Calculate first, interpret second.
Your placements come from a deterministic open astronomy engine. AI is a translation layer, not the source of truth.
Show the source.
Every interpretation is paired with the chart facts that grounded it — clickable chips that highlight the placements being read.
Reflective, not predictive.
ChartLumen is for self-reflection and entertainment. It declines medical, legal, financial, crisis, and certainty-based future advice.
Privacy by default.
Exact birth date, time, and place stay hidden on shared profiles unless you explicitly turn them on. Charts are session-scoped unless you sign in and choose to save.
What we build on
astronomy-engine
MIT-licensed planetary calculations.
OpenStreetMap Nominatim
Place search and reverse geocoding for birthplace lookup.
tz-lookup
Time-zone resolution from latitude/longitude.
Vercel AI Gateway
Streamed AI interpretation, structured output via zod schemas.
Why this isn’t a horoscope app
Horoscope apps generalize across millions of people sharing a Sun sign. ChartLumen reads the actual chart you were born under — Sun, Moon, Rising, all 10 planets, lunar nodes, retrograde state, aspects, and (when you’re in Vedic mode) Navamsa, Vimshottari Mahadasha, and nakshatras. Every claim cites a specific placement.