78 live calculation APIs · built for trusted backends

One astrology API platform for charts, timing, events, and research tools

R231 is live: 77 standard calculations plus the Pro Nakshatra Timeline are available, with the 500-request Free allowance and globally serial durable jobs.

Build Western, sidereal, and Vedic-oriented applications with documented JPL DE421 calculations. Generate chart data and graphics, search bounded astrological events, create reports, and automate trusted server workflows through one API.

  • 39 live standard calculations on every plan, plus Pro Nakshatra Timeline
  • 14 durable-job operations with the same scopes, budgets, and quota accounting
  • 500 Free requests per month; paid plans start at $9.99/month
52
Live calculations
13
Durable-job operations
3
Sidereal modes
SOURCE CANDIDATE Sample API Request
// Run on your server; store the key in ASTROAPI_KEY
const response = await fetch("https://api.cosmicephemeris.com/api/astro/birth-chart", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    "Authorization": `Bearer ${process.env.ASTROAPI_KEY}`
  },
  signal: AbortSignal.timeout(20000),
  body: JSON.stringify({
    date: "2000-01-01",
    time: "12:00",
    lat: 0.0,
    lon: 0.0,
    timezone: "UTC"
  })
});
if (!response.ok) throw new Error(`Cosmic Ephemeris HTTP ${response.status}`);
const data = await response.json();
console.log(data.chart);
# Run on your server; store the key in ASTROAPI_KEY
import os
import requests

url = "https://api.cosmicephemeris.com/api/astro/birth-chart"

payload = {
  "date": "2000-01-01",
  "time": "12:00",
  "lat": 0.0,
  "lon": 0.0,
  "timezone": "UTC"
}

headers = {
  "Content-Type": "application/json",
  "Authorization": f"Bearer {os.environ['ASTROAPI_KEY']}"
}

response = requests.post(url, json=payload, headers=headers, timeout=20)
response.raise_for_status()
print(response.json()["chart"])

The Cosmic Ephemeris production platform

Market-ready building blocks across 78 live calculations

Start with established chart endpoints, then add explicitly bounded beta calculations and developer workflows without changing providers.

Core chart data

Charts, houses, aspects, and transits

Generate tropical or sidereal natal charts, houses, aspects, transits, synastry, and structured horoscope signals as server-side JSON.

Explore all calculation APIs

Western relationships + timing

From composites to solar arcs

Build with midpoint composites, uncorrected Davison charts, secondary progressions, solar arcs, returns, lunar nodes, and SVG/PNG chart rendering.

Explore Western tools

Sidereal + Vedic-oriented

Vargas, Vimshottari, Panchang, and matching

Select Lahiri, Raman, Krishnamurti, Fagan–Bradley, Yukteshwar, Sassanian, True Chitra, True Revati, True Pushya, Galactic Center at 0 Sagittarius, or Galactic Alignment/Mardyks; calculate twenty-four Vargas through D150, Vimshottari through optional depth 4, instant Panchang, Ashtakoota, Ashtakavarga with opt-in reductions and pindas, and Pro timelines.

Explore Vedic-oriented tools

Event search + calendars

Search, save, schedule, and deliver

Filter unified calendars and aspect windows, save reusable criteria, run them daily or weekly as globally serial durable jobs, export results, and deliver completion through signed webhooks.

Explore Event Intelligence

Geography + reports

Relocation, astrocartography, analysis, and output

Calculate relocation charts, bounded astrocartography lines with downloadable SVG/PNG coordinate-grid maps, configurable natal analysis, fact-linked HTML/PDF/DOCX/XLSX/ODS/EPUB/ODT/RTF/JSON/CSV/XML/NDJSON/TSV/Markdown/plain-text/ZIP reports, birth-time sensitivity, and six admitted fixed stars.

Explore application use cases

Birth-data onboarding

Place search and historical timezone resolution

Search a pinned self-hosted place catalog, select a versioned ID, and resolve the local historical clock under a pinned IANA timezone release without guessing daylight-saving folds or gaps.

Explore onboarding APIs

Auditable context

Deterministic facts for your chosen model

Generate compact JSON, XML, or Markdown fact bundles with stable IDs, source paths, declared conventions, calculation fingerprints, and artifact hashes—without generated advice.

Review accuracy and reproducibility

Developer platform

Durable jobs, MCP, teams, webhooks, and controls

Run fourteen fixed job operations through JSON or bounded NDJSON, connect trusted agent hosts to all 78 live calculations, and manage projects, budgets, workspaces, saved inputs, signed webhooks, and integrity-checked report downloads.

Explore the developer platform

Explore the calculation tools for your tradition

Start with the zodiac and house system you need, then review the supported features.

Sidereal astrology

Select Lahiri, Raman, Krishnamurti, Fagan–Bradley, Yukteshwar, Sassanian, True Chitra, True Revati, True Pushya, Galactic Center at 0 Sagittarius, or Galactic Alignment/Mardyks ayanamsa for sidereal longitudes, signs, chart angles, houses, and Moon nakshatra data.

See a sidereal birth chart request

Vedic / Jyotish building blocks

Build from sidereal charts and nakshatra/pada geometry, with Pro transition timelines for nine bodies. Explore beta D1/D2/D3/D4/D5/D6/D7/D8/D9/D10/D11/D12/D16/D20/D24/D27/D30/D40/D45/D60/D81/D108/D144/D150, Vimshottari through optional Sookshma depth 4, Indian chart SVGs and instant Panchang with explicit conventions. Regional calendars, festivals and complete Jyotish analysis remain outside the current scope.

Chart graphics, Western and Vedic beta APIs

Pratyantardasha inputs and period conventions

Davison relationship chart conventions

Moon phases and iCalendar exports

Planetary ingresses, stations, and exact aspects

Fixed-reference house ingress search

Planetary aspect orb windows and calendar export

Explore the nakshatra timeline API

Frequently Asked Questions

Clear answers to the questions developers actually ask.

Can I start for free?

Free includes 500 standard API requests per UTC calendar month with no credit card required. Tropical and sidereal chart calculations are included.

What features are available?

Cosmic Ephemeris exposes 78 live calculation endpoints: seven established routes and seventy-one bounded beta routes. Coverage includes natal charts, houses, aspects, transits, synastry and structured horoscope signals; chart SVG/PNG; composites, Davison, progressions, solar arcs, returns and lunar nodes; twenty-four Vargas, Vimshottari through optional depth 4, Panchang, Ashtakoota, and Ashtakavarga with opt-in reductions and pindas; Moon phases, planetary events, house ingresses, aspect windows, unified calendars, eclipse and electional searches; bounded electional reliability audits through exact repair-hardening minimax regret; relocation, astrocartography, natal analysis, reports, birth-time sensitivity and six fixed stars; and symbolic numerology arithmetic without predictions. Seventy-seven standard calculations are available on every plan; Nakshatra Timeline requires Pro.

What developer-platform features are included?

All plans can use server-side API keys, projects, development/staging/production controls, per-key budgets, saved chart inputs, team workspaces, signed job-completion webhooks, deterministic report downloads and MCP access to all 78 live calculations. Durable jobs accept one to ten items from fourteen fixed operations through JSON or bounded NDJSON, with the same scopes, budgets, quotas and one-unit-per-item accounting as synchronous calls.

Does Cosmic Ephemeris support Western and Vedic astrology?

Cosmic Ephemeris supports tropical calculations for Western astrology and sidereal charts with Lahiri, Raman, Krishnamurti, Fagan–Bradley, Yukteshwar, Sassanian, True Chitra, True Revati, True Pushya, Galactic Center at 0 Sagittarius, or Galactic Alignment/Mardyks ayanamsa. Moon nakshatra/pada data and beta D1/D2/D3/D4/D5/D6/D7/D8/D9/D10/D11/D12/D16/D20/D24/D27/D30/D40/D45/D60/D81/D108/D144/D150, Vimshottari, Indian SVG and instant Panchang calculations support Vedic-oriented applications. Panchang uses an explicit USNO solar-event model and latitude limits; regional calendars, festivals and a complete Jyotish system are not provided.

Which house systems and dates are supported?

Equal and whole-sign houses are supported, with opt-in beta Placidus and Porphyry that reject undefined geometry without a fallback. Porphyry is limited to the Houses and natal-SVG endpoints. Public calculation dates run from January 1, 1900 through December 31, 2050. Supply an IANA timezone for local birth times; omitted timezones default to UTC.

Does Cosmic Ephemeris calculate solar-arc directions?

Yes. The beta solar-arc endpoint rotates natal planets and Ascendant/MC by the true tropical solar arc, with tropical or sidereal output and synthetic equal or whole-sign houses. It does not calculate physical event charts, converse directions or predictions. Each admitted calculation uses one standard request.

Does Cosmic Ephemeris support Pratyantardasha?

Yes. The beta Vimshottari endpoint returns major periods and Antardasha by default. Depth 3 adds 729 Pratyantardashas; depth 4 adds 6,561 bounded Sookshma periods. It uses a fixed 365.25-day year, supports Lahiri, Raman, Krishnamurti, Fagan–Bradley, Yukteshwar, Sassanian, True Chitra, True Revati, True Pushya, Galactic Center at 0 Sagittarius, and Galactic Alignment/Mardyks ayanamsas, and costs one standard request per admitted synchronous calculation. Other dasha systems and deeper levels are not supported.

Are more sidereal systems, Moon phases, asteroids and fixed stars included?

Cosmic Ephemeris currently supports Lahiri, Raman, Krishnamurti, Fagan–Bradley, Yukteshwar, Sassanian, True Chitra, True Revati, True Pushya, Galactic Center at 0 Sagittarius, and Galactic Alignment/Mardyks ayanamsas, not every sidereal system offered by other products. The six-star-only CC0 beta is available; asteroid and minor-body calculations are not offered. Separate betas provide Moon-phase calendars, bounded global eclipse geometry and hourly electional filtering. They do not provide local eclipse visibility or paths, crescent visibility, continuous electional guarantees, rankings or advice. Solar/lunar returns find natal-longitude returns, not new or full moons.

Can I use Cosmic Ephemeris in my application?

You may integrate documented results into your application subject to the Terms; reselling raw API access is not permitted.

How do I authenticate?

Authorization: Bearer <YOUR_API_KEY>

What languages are supported?

Any language capable of sending HTTPS requests.

How accurate is the data?

Planetary positions use the bundled JPL DE421 ephemeris. House angles and lunar-node fields use documented engine approximations; see the calculation methodology for scope.

Can I change plans later?

Yes. Use Stripe's hosted billing portal to change plans or cancel. Plan changes are prorated, and cancellation takes effect at the end of the current billing period.

Is my API key secure?

API keys are returned once, stored only as one-way SHA-256 hashes, and transmitted over HTTPS. Keep them on your server.

Technology partners

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Each partner keeps its own application, accounts, credentials, subscriptions, data, and policies.

Partnered with TimeMatrix

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TimeMatrix brings advanced market charting, Gann tools, and financial-astrology research into one browser-based workspace.

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Partnered with FilingSift

Find the material change inside an SEC filing.

FilingSift turns selected debt, liquidity, covenant, waiver, and going-concern disclosures into source-cited, machine-readable changes.

Independent API and data product. Not investment advice.

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