Free Astrology API (freeastrologyapi.com) markets itself on its name: free to start, with a 50-request-per-day free tier and paid plans named after planets. It is one of the lower-friction ways to start prototyping an astrology app. The question for any team picking an API is whether the free entry point is the right call once you cross into production traffic.
TL;DR comparison
| Dimension | Astrology API | Free Astrology API |
|---|---|---|
| Free tier | 50 requests/month (permanent, no card) | 50 requests/day, 1 req/sec |
| Paid entry | $11/mo (1,000 requests) | $15/mo (50,000 requests, 10 req/sec) |
| Mid tier | $37/mo (55,000 requests) | $40/mo (200,000 requests, 100 req/sec) |
| Top tier | $99/mo (220,000 requests) | $75/mo (500,000 requests, 1,000 req/sec) |
| Annual discount | Available on enterprise | 18% off annual |
| Endpoints | 100+ | ~30 across Vedic and Western |
| House systems | 23 | ~6 in standard endpoints |
| Languages | 9+ output languages | Multiple via parameters |
| Response time | ~300ms median | 500–900ms median |
| Ephemeris | Swiss Ephemeris (DE431-derived) | Swiss Ephemeris-based |
| OpenAPI spec | Yes | No public OpenAPI file |
| Best for | Multi-tradition, OpenAPI workflows, deep Western | Cost-sensitive teams with high request volume needs |
What each provider is
Both are real APIs with active customers. The trade-off is breadth versus raw request volume per dollar.
Pricing in detail
- Free: $0/mo, 50 requests/day, 1 req/sec
- Mercury: $15/mo, 50,000 requests/mo, 10 req/sec
- Venus: $40/mo, 200,000 requests/mo, 100 req/sec
- Saturn: $75/mo, 500,000 requests/mo, 1,000 req/sec
- Enterprise: custom
All paid tiers include unlimited public and private projects, email support, and an 18% discount on annual billing.
Astrology API's tiers:
- Free: $0/mo, 50 requests/mo (permanent, no card)
- Starter: $11/mo, 1,000 requests
- Professional: $37/mo, 55,000 requests
- Business: $99/mo, 220,000 requests (all endpoints)
- Enterprise: $399+/mo, unlimited with dedicated capacity
Cost at two scale points
The trade-off: Free Astrology API gives you more requests per dollar; Astrology API gives you broader coverage and lower latency per request.
Endpoint coverage
- Vedic: kundli, planetary positions (sidereal), divisional charts (D1, D9, others), dasha periods (vimshottari), panchang
- Western: natal chart, planetary positions (tropical), houses, aspects, synastry
- Horoscopes: daily/monthly text feeds
- KP astrology: KP chart, significators
Astrology API ships 100+ endpoints:
- Western natal in 23 house systems with Arabic parts (97+), fixed stars, asteroids, midpoints, antiscia
- Predictive: secondary progressions, solar arc, primary directions, profections, zodiacal releasing, solar/lunar/Venus returns
- Synastry, composite, Davison, harmonics, draconic
- Astrocartography: ACG lines, parans, local space, relocation
- Vedic: kundli, full divisional chart set, dashas (vimshottari and more), nakshatra, navamsa, panchang
- KP astrology with significator and sub-sub-lord calculations
- Chinese: BaZi (Four Pillars), Zi Wei Dou Shu, Chinese zodiac, flying stars, Feng Shui
- Tarot (multiple spreads), numerology (Pythagorean, Chaldean, Lo Shu), human design, palm reading
If you only need core natal + Vedic, Free Astrology API has the relevant endpoints. If you need advanced Western techniques (Arabic parts, harmonics, primary directions, astrocartography) or non-Western traditions (Chinese, Tarot, Numerology), Astrology API has them; Free Astrology API does not.
A real example: zodiacal releasing — a Hellenistic predictive technique — is available on Astrology API as a single call. Free Astrology API does not expose it.
Performance and accuracy
Response time observations:
- Astrology API: ~300ms median for natal endpoints from US/EU regions
- Free Astrology API: 500–900ms median; faster from regions closer to its origin servers, slower from US West Coast
The rate-limit ceiling matters more than the median for many apps. Free Astrology API's free tier caps at 1 req/sec, Mercury at 10 req/sec, Venus at 100 req/sec, Saturn at 1,000 req/sec. If your app has a daily spike — say morning horoscope checks at 8am — you can hit the per-second ceiling well before your monthly quota fills.
Astrology API's per-tier rate limits scale with the request count, with burst headroom on Business and Enterprise plans. For real-time apps with spiky traffic, the burst headroom matters.
Developer experience
Free Astrology API uses standard REST with JSON request bodies and API key authentication. The docs are organized by endpoint with curl examples and live test panels. There is no public OpenAPI spec file as of this writing, so client generation is hand-rolled or via community libraries.
Astrology API ships an OpenAPI 3.0 spec. Standard tooling (openapi-generator, Postman, Insomnia, IDE plugins) works out of the box. Responses use a consistent JSON envelope across endpoints. Errors are structured with HTTP status codes plus a typed error body.
Both have sandbox/test functionality. Both have email support on paid plans. Free Astrology API's docs are simpler and easier to skim if you only need a few endpoints. Astrology API's docs are deeper and benefit from the consistent schema across the full surface area.
When to choose Astrology API
Pick Astrology API if any of these apply:
- You need advanced Western techniques (Arabic parts, harmonics, primary directions, profections, zodiacal releasing)
- You need astrocartography, Chinese astrology, Tarot, or numerology in the same bill
- You need sub-500ms response time from US/EU regions
- You want flat tiers with included Business-plan features (all endpoints, all house systems)
- You want an OpenAPI spec for tooling and client generation
- You need 23 house systems for professional astrologer customers
The breadth premium matters once you start adding features. Adding "secondary progressions" to your app should be a one-endpoint call, not a workaround.
When to choose Free Astrology API
Pick Free Astrology API if any of these apply:
- Your traffic is cost-sensitive and you need 200,000+ requests/month on a tight budget
- Your endpoint mix is narrow (natal + Vedic, or natal + synastry, or daily horoscopes)
- You are okay with 500–900ms latency
- The 18% annual discount appeals to you and your team can commit to yearly billing
- You are prototyping and want the most generous truly-free tier in the market for the first month
The pricing is genuinely competitive at the volume points where Free Astrology API's tiers are calibrated. If you fit the use case, the savings are real.
Migration notes
For teams moving from Free Astrology API to Astrology API, the calculation output is closely aligned because both use Swiss Ephemeris. The main differences are in request/response shape and authentication.
High-level endpoint mapping:
| Free Astrology API | Astrology API equivalent |
|---|---|
/planets (tropical) | /v1/natal/planets |
/planets/extended | /v1/natal/chart |
/sidereal-planets | /v1/vedic/planets |
/houses | /v1/natal/houses |
/aspects | /v1/natal/aspects |
/horoscope-data | /v1/horoscope/daily |
/d1-chart-info | /v1/vedic/birth-chart |
/d9-chart-info (Navamsa) | /v1/vedic/navamsa |
/vimshottari-dasha | /v1/vedic/vimshottari-dasha |
/panchang | /v1/vedic/panchang |
Auth migration: Free Astrology API uses a header API key. Astrology API uses a bearer token. The change is one line.
Date format: both accept ISO 8601 with timezone offset. Confirm your timezone handling matches.
Things to verify before you cut over
A few practical checks save time during migration:
- Confirm your house system on both sides. Free Astrology API often defaults to Placidus for Western and Whole Sign for Vedic. Astrology API accepts a
house_systemparameter on every chart endpoint; default is Placidus. If your displayed cusps suddenly change after migration, this is usually why. - Confirm your ayanamsa for sidereal/Vedic calls. Lahiri is the common default; KP uses a different offset. Set explicitly to remove ambiguity.
- Test with a small set of known charts (your team's birth data, a few public-figure charts) and diff the planetary positions, house cusps, and aspect lists. They should match within seconds of arc.
- Re-run any cached output. If you cached responses keyed by request hash, the keys change because request bodies differ slightly.
FAQ
Is Free Astrology API actually free?
Does Free Astrology API have astrocartography?
Which API is faster?
Astrology API. The median is ~300ms versus 500–900ms on Free Astrology API. For a user-facing real-time UI, the difference is noticeable. For background jobs or batch processing, either is fine.
Can I use Free Astrology API for commercial products?
Yes, paid plans include commercial use. Read the current terms of service before launch.
Which API has more endpoints?
Astrology API has more unique calculation types (100+ versus ~30). Free Astrology API covers the most common Vedic and Western endpoints; Astrology API adds Chinese astrology, advanced Western techniques, astrocartography, Tarot, numerology, and other categories.
