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12andus Astrology

Lifestyleby Apogeeks Pte. Ltd.

12andus Astrology delivers professional-grade astrological insights powered by precise calculations and personalized charts analysis.

What You Can Explore

Personality & Psychological Insights Discover your strengths, challenges, emotional patterns, and inner motivations based on your unique birth chart. Understand how you think, love, work, and make decisions through the lens of your planetary placements.

Timing Guidance & Forecasts Receive personalized transit forecasts for up to one year ahead, revealing upcoming periods of growth, change, opportunity, or challenge. See when key planetary influences begin and end.

Relationship Compatibility Explore the dynamics between you and anyone else through synastry analysis (how your charts interact) and composite charts (the unique energy your relationship creates together). For romantic relationships, understand the chemistry of attraction, emotional compatibility, communication styles, intimacy patterns, and long-term potential. The same depth of analysis applies to any relationship — family bonds, friendships, business partnerships, or professional collaborations. See where you naturally harmonize, where friction may arise, and how to navigate differences with greater awareness.

Relationship Timing Go beyond static compatibility — see how transiting planets activate your composite chart, revealing the best times for important relationship milestones, conversations, or decisions.

Key Features

  • Private Birth Data Storage — Securely save up to 50 birth charts under your account for instant access to readings without re-entering data
  • Birth Charts — Complete natal analysis including planets, houses, aspects, and retrograde positions
  • Transit Charts — Forecasts from 1 day to 365 days showing active planetary influences
  • Relationship Charts — Synastry and composite analysis between any two saved people
  • Relationship Forecasts — Transits to composite charts revealing relationship timing

Unmatched Precision 12andus calculations consider the exact planetary positions based on your specific birth date, time, and place. When birth time is unknown, the system adapts intelligently, providing insights without house-dependent data.

Holistic Readings Unlike fragmented interpretations that list placements one by one, 12andus synthesizes your chart holistically — weaving together planetary positions, aspects, and houses into a unified narrative that reflects how these energies actually work together in your life.

13ChatGPT Tools
Apogeeks Pte. Ltd.Developer
LifestyleCategory

Available Tools

Delete Birth Chart

delete_birth_chart
Full Description

Delete a saved birth chart by name.

Uses the user's email from sign-in automatically.

Parameters (1 required)
Required
namestring

Calculate Birth Chart

get_birth_chart
Full Description

Calculate and ANALYZE a birth chart with interpretation and visual chart images.

Parameters (7 required, 5 optional)
Required
dayinteger
latitudenumber
longitudenumber
monthinteger
namestring

Person's name

timezonestring
yearinteger
Optional
birth_time_knownboolean
hourinteger
languagestring
Default: en
location_namestring
minuteinteger

Get Chart Images

get_chart_images
Full Description

⭐ VISUAL CHART DISPLAY

  • Use this tool when user wants to SEE, SHOW, VIEW, or DISPLAY a birth chart wheel or aspect grid.

ALWAYS USE THIS TOOL for visual/display requests like:

  • "show [name]'s chart wheel"
  • "display [name]'s birth chart"
  • "can I see [name]'s chart"
  • "view the wheel for [name]"
  • "show me the aspect grid"

Requirements: Person must have saved birth data. Use list_saved_charts to check. NOT for: Calculating new charts (use get_birth_chart) or analysis/interpretation (use get_birth_chart).

Returns an interactive visual widget with zoomable chart wheel and aspect grid images.

Parameters (1 required)
Required
namestring

Get Forecast

get_forecast
Full Description

Get astrological forecast showing planetary transits affecting the person.

birth_time_known is optional - auto-inferred from whether hour is provided.

Use this when the user asks about TIMING: 'today', 'this week', 'this month', 'next 3 months', 'what's coming up', or any future-oriented question.

Parameters:

  • forecast_date: Start date in YYYY-MM-DD format (use today's date for 'now')
  • days: Number of days to analyze (1-365). Use 1 for today, 7 for week, 30 for month, etc.
Parameters (9 required, 5 optional)
Required
dayinteger
daysinteger
forecast_datestring
latitudenumber
longitudenumber
monthinteger
namestring
timezonestring
yearinteger
Optional
birth_time_knownboolean
Default: null
hourinteger
Default: null
languagestring
Default: en
location_namestring
minuteinteger
Default: null

Get Memes

get_memes
Full Description

Get personalized astrology memes based on birth chart placements.

Returns a gallery of memes tailored to the person's unique astrological profile. Great for fun, shareable content based on their Sun sign, aspects, and placements.

Parameters (7 required, 5 optional)
Required
dayinteger
latitudenumber
longitudenumber
monthinteger
namestring
timezonestring
yearinteger
Optional
hourinteger
Default: null
languagestring
Default: en
limitinteger
Default: 10
location_namestring
minuteinteger
Default: null

Get Relationship

get_relationship
Full Description

🔴 USE THIS for "compare X with Y" - gives SYNASTRY + COMPOSITE chart analysis.

This is the CORRECT tool for relationship/compatibility. Returns:

  • Synastry aspects (how their charts interact)
  • Composite chart (the relationship as its own entity)

🚫 DO NOT call get_birth_chart twice for comparisons - that's WRONG! Call get_relationship ONCE with both people's data.

⚠️ PARAMETER FORMAT: All parameters are FLAT (not nested objects). Example: person1_name="Carlo", person1_day=4, person1_month=4, person1_year=1977, ... person2_name="Jiab", person2_day=21, person2_month=6, person2_year=1977, ...

🔴 WORKFLOW for "compare X with Y": 1. If you just calculated X's chart → you have their data in memory, USE IT 2. Call list_birth_charts to check if Y is saved → if yes, use that data 3. Call THIS tool with FLAT params for BOTH people 4. After response, offer to save any unsaved person

birth_time_known is optional - auto-inferred from whether hour is provided.

Parameters (14 required, 7 optional)
Required
person1_dayinteger
person1_latitudenumber
person1_longitudenumber
person1_monthinteger
person1_namestring
person1_timezonestring
person1_yearinteger
person2_dayinteger
person2_latitudenumber
person2_longitudenumber
person2_monthinteger
person2_namestring
person2_timezonestring
person2_yearinteger
Optional
languagestring
Default: en
person1_birth_time_knownboolean
Default: null
person1_hourinteger
Default: null
person1_minuteinteger
Default: null
person2_birth_time_knownboolean
Default: null
person2_hourinteger
Default: null
person2_minuteinteger
Default: null

Get Relationship By Names

get_relationship_by_names
Full Description

Relationship compatibility using SAVED charts only. Both people MUST already be saved.

🚫 DO NOT use this if you just calculated someone's chart in this conversation! 🚫 DO NOT use this without checking list_birth_charts first!

USE THIS ONLY when:

  • You have NOT calculated any charts in this conversation
  • User mentions two names that are BOTH definitely saved

🔴 IF YOU JUST CALCULATED SOMEONE'S CHART: → Use get_relationship instead (you have their data in memory!) → Call list_birth_charts to get the other person's saved data → Then call get_relationship with BOTH people's full data

Example: User says "chart for Carlo" then "compare with Jiab" → You have Carlo's data (just calculated!) → Call list_birth_charts → find Jiab's saved data → Call get_relationship with Carlo + Jiab data (NOT this tool!)

Parameters (2 required, 1 optional)
Required
person1_namestring
person2_namestring
Optional
languagestring
Default: en

Get Relationship Forecast

get_relationship_forecast
Full Description

Get relationship timing forecast with transits to composite chart. Use for relationship timing questions. forecast_date should be YYYY-MM-DD format. days is 1-365.

birth_time_known is optional - auto-inferred from whether hour is provided.

CRITICAL: This tool only works with EXACTLY 2 people. If user mentions 3+ people:

  • STOP - do NOT call this tool
  • do NOT call this tool multiple times for different pairs
  • do NOT make up or hallucinate forecast data
  • Ask user which pair to compare and WAIT for their response
Parameters (16 required, 7 optional)
Required
daysinteger
forecast_datestring
person1_dayinteger
person1_latitudenumber
person1_longitudenumber
person1_monthinteger
person1_namestring
person1_timezonestring
person1_yearinteger
person2_dayinteger
person2_latitudenumber
person2_longitudenumber
person2_monthinteger
person2_namestring
person2_timezonestring
person2_yearinteger
Optional
languagestring
Default: en
person1_birth_time_knownboolean
Default: null
person1_hourinteger
Default: null
person1_minuteinteger
Default: null
person2_birth_time_knownboolean
Default: null
person2_hourinteger
Default: null
person2_minuteinteger
Default: null

Get Relationship Forecast By Names

get_relationship_forecast_by_names
Full Description

PREFERRED: Get relationship timing forecast using saved birth data. Just provide the two names.

CRITICAL: This tool only works with EXACTLY 2 people. If user mentions 3+ people:

  • STOP - do NOT call this tool
  • do NOT call this tool multiple times for different pairs
  • Instead, respond: "I can only analyze relationships between two people at a time. Which pair would you like me to compare?"
  • WAIT for the user to choose before calling this tool

forecast_date should be YYYY-MM-DD format. days is 1-365. Automatically looks up saved birth charts. If either person is not found, tells you which data is missing.

Parameters (4 required, 1 optional)
Required
daysinteger
forecast_datestring
person1_namestring
person2_namestring
Optional
languagestring
Default: en

List Birth Charts

list_birth_charts
Full Description

Get user's saved birth charts with FULL birth data (all fields needed for get_relationship).

🔴 CALL THIS when user says "compare with [name]" to get that person's saved data.

Returns complete data: name, day, month, year, hour, minute, latitude, longitude, timezone. Use this data directly in get_relationship calls.

Example: User says "compare Carlo with Jiab" → You have Carlo's data (just calculated) → Call list_birth_charts → find Jiab with full birth data → Call get_relationship(person1=Carlo data, person2=Jiab data from this result)

Save Birth Chart

save_birth_chart
Full Description

Save birth data for future readings. THIS TOOL IS AVAILABLE - use it!

Stores name, birth date/time, and location under the user's account. After saving, the person can be referenced by name in get_relationship_by_names.

birth_time_known is optional - if not provided, it's inferred from whether hour is given.

🔴 ALWAYS offer to save after calculating a new chart (get_birth_chart or view_chart_visual). Example: "Would you like me to save Mauro's chart for future readings?"

Useful for quick access to readings without re-entering data each time.

Parameters (7 required, 4 optional)
Required
dayinteger
latitudenumber
longitudenumber
monthinteger
namestring
timezonestring
yearinteger
Optional
birth_time_knownboolean
Default: null
hourinteger
Default: null
location_namestring
minuteinteger
Default: null

Search Location

search_location
Full Description

Search for a city/location and get precise coordinates and timezone.

WHEN TO USE THIS TOOL:

  • Small towns, villages, or neighborhoods you're not 100% confident about
  • Places outside major world cities
  • When user specifies a district/area within a city (e.g., "Brooklyn, NY" or "Shibuya, Tokyo")
  • Any place where you're uncertain about exact coordinates
  • When precise coordinates matter (they always do for astrology!)

For major world capitals (London, Paris, Tokyo, New York) you may use your knowledge, but for anything smaller, USE THIS TOOL to ensure accuracy.

Returns cities with latitude, longitude, and timezone needed for birth charts.

Parameters (1 required)
Required
querystring

View Chart Visual

view_chart_visual
Full Description

Generate visual birth chart (wheel image + aspect grid) for ONE person.

Use when user says "show/see/view chart" with birth data. For text analysis/interpretation, use get_birth_chart instead.

🔴 MANDATORY AFTER THIS TOOL

  • YOU MUST:

1. End response with: "Would you like me to save [name]'s chart for future readings?" 2. Offer: "I can explain the chart or compare with someone else."

🔴 REMEMBER the birth data for later use in get_relationship.

Parameters (7 required, 4 optional)
Required
dayinteger
latitudenumber
longitudenumber
monthinteger
namestring
timezonestring
yearinteger
Optional
hourinteger
Default: null
languagestring
Default: en
location_namestring
minuteinteger
Default: null