This comparison has an asterisk: AstroSeek is not actually a developer API. It is a popular free consumer astrology website at astro-seek.com. The site offers natal charts, transits, synastry, horary, electional, and a long list of calculators that have made it a go-to research tool for astrologers — but there is no public REST API, no SDK, no OAuth, no documented endpoints.
Developers still search for "AstroSeek API" because the site is so feature-rich. So this article does two jobs: it covers what AstroSeek actually offers, and it explains what your real options are when you need that depth in your own app.
TL;DR comparison
| Dimension | Astrology API | AstroSeek |
|---|---|---|
| Public API | Yes (REST, OpenAPI 3.0) | No |
| Pricing | $0–$399+/mo | Free for site use |
| Authentication | API key (bearer) | None (website only) |
| Endpoints | 100+ | Not applicable |
| House systems | 23 | ~6 in UI |
| Languages | 9+ output languages | ~10 in UI |
| Response time | ~300ms median | Browser-only |
| Ephemeris | Swiss Ephemeris (DE431-derived) | Swiss Ephemeris-based |
| OpenAPI spec | Yes | No |
| Commercial use in your app | Yes | Not permitted via scraping |
| Best for | Production apps, mobile, SaaS, batch | Personal research, manual chart work |
What each provider is
These are different products solving different problems. If you are a working astrologer who wants to look at a chart, AstroSeek is excellent. If you are a developer who wants to put astrology features in front of 10,000 users, you need an API.
Pricing in detail
Astrology API uses a tiered per-request model:
- Free: $0/mo, 50 requests (always free, no card required)
- 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 honest framing: AstroSeek is "free" only if your usage is manual and personal. Once you need programmatic access, AstroSeek's effective cost is "not available at any price, and trying to work around it is risky."
Endpoint coverage
This is where the comparison gets interesting, because feature parity is the real question developers are asking when they search for "AstroSeek API." Here is what AstroSeek offers in its UI, mapped to Astrology API endpoints.
| AstroSeek feature | Astrology API equivalent |
|---|---|
| Natal chart with custom house systems | Natal API — 23 house systems |
| Synastry chart | Synastry API |
| Composite chart | /v1/composite/chart |
| Davison chart | /v1/davison/chart |
| Transits (current and custom date) | Transit API |
| Secondary progressions | /v1/progressions/secondary |
| Solar arc directions | /v1/directions/solar-arc |
| Solar return | /v1/returns/solar |
| Lunar return | /v1/returns/lunar |
| Harmonic charts | /v1/harmonics/chart |
| Draconic chart | /v1/natal/chart?zodiac=draconic |
| Horary chart | /v1/horary/chart |
| Electional astrology | /v1/electional/search |
| Fixed stars | /v1/natal/fixed-stars |
| Arabic parts (Lots) | /v1/natal/arabic-parts (97+) |
| Asteroids | /v1/natal/asteroids |
| Midpoints | /v1/natal/midpoints |
| Antiscia | /v1/natal/antiscia |
| Vedic chart and dashas | Vedic API |
| Astrocartography | Astrocartography API |
| Chinese BaZi | Chinese BaZi |
Where Astrology API goes beyond AstroSeek:
- 23 house systems versus the ~6 in AstroSeek's standard UI
- 97+ Arabic parts as a structured endpoint
- AI-powered interpretations as an opt-in endpoint
- Full astrocartography (lines, parans, local space) as a single call
- Chinese BaZi and Zi Wei Dou Shu as first-class endpoints
- Tarot, numerology, and palm reading endpoints
Where AstroSeek has its own niche:
- Specialty calculators that astrologers like (e.g., custom planet sets, custom aspect orbs in the UI)
- A rich free-text horary interpretation feature
- A long history of community use, making the calculator output familiar to astrologers
You can replicate most of AstroSeek's calculation output in your own app using Astrology API. You cannot, of course, replicate the consumer UI — that is AstroSeek's product, not their data.
Performance and accuracy
Performance is a non-comparison because AstroSeek is not an API. A typical AstroSeek chart page renders in 1–3 seconds in a browser, including HTML, CSS, and inline rendering. A backend call to Astrology API for the same data returns in ~300ms with a clean JSON payload that you parse and render yourself.
If you scrape AstroSeek (which you should not), your effective response time is whatever the page render takes plus your HTML parsing overhead, with the added risk of layout changes and rate limiting.
Developer experience
Astrology API ships an OpenAPI 3.0 specification, which means standard tooling: generate clients with openapi-generator, import directly into Postman or Insomnia, get autocomplete in your IDE. Authentication is a simple bearer API key. Responses use a consistent JSON envelope across endpoints.
AstroSeek has no developer experience because there is no developer product. There is no key, no docs, no SDK, no rate limit policy, no SLA, and no support channel for developers. The site's contact page is for general inquiries.
This is not a knock on AstroSeek. They never positioned themselves as a developer platform. They are a consumer site with a deep feature set, and they have served that purpose well for over a decade.
When to choose Astrology API
Pick Astrology API if any of these apply:
- You are building a product that needs astrology data via an API
- You need 23 house systems, harmonics, Arabic parts, or astrocartography in production
- You want predictable per-request pricing with a generous free tier
- You need response times under 500ms for a real-time UI
- You want an OpenAPI spec, structured errors, and SDKs in multiple languages
- You need a vendor with documented uptime and a support channel
When to choose AstroSeek
Pick AstroSeek if any of these apply:
- You are an astrologer (or hobbyist) who wants free chart calculations in a browser
- You are doing research and need a wide feature set without writing code
- You want to compare a few calculation outputs against another source
- You are a student learning techniques and want a free calculator that supports them
- You need a manual horary or electional workup right now
AstroSeek is a great free tool for what it is. It is just not a tool you can build a product on top of.
Migration notes
You cannot "migrate" from AstroSeek to Astrology API in the usual sense — there are no API calls to swap out. But if you are a developer who has been doing manual lookups on AstroSeek and pasting results into your app, here is the rough path:
- Pick the AstroSeek techniques you actually use (natal, transits, synastry, etc.).
- Map them to Astrology API endpoints using the table above.
- Replace manual lookup with an API call. Most developers find this takes 30 minutes per technique.
- If you were copying interpretations from AstroSeek's free-text output, do not do that for a commercial product — that content is not licensed for redistribution. Use Astrology API's interpretation endpoints or write your own.
FAQ
Does AstroSeek have an API?
Can I scrape AstroSeek for my app?
Technically you can write a scraper. You should not. AstroSeek's terms of service prohibit automated access, the page structure changes without notice, and there is no SLA — if AstroSeek goes down, your app goes down. Plus, the calculations themselves come from Swiss Ephemeris, which you can access directly through a proper API like Astrology API.
Is AstroSeek more accurate than Astrology API?
Both run on Swiss Ephemeris, which derives from NASA JPL's DE431 ephemeris. Planet positions and house cusps match to fractions of an arcsecond. There is no meaningful accuracy difference for any technique they both support.
Can I license AstroSeek's calculations?
What about AstroSeek's free reports?
AstroSeek's free-text reports (compatibility, personality, etc.) are written content tied to their site. They are not available as an API and are not licensed for redistribution. If you need text interpretations, Astrology API's interpretation endpoints generate per-chart output you can ship in your app.
Why do people still search for "AstroSeek API"?
Because AstroSeek's feature set is impressive and developers naturally assume a popular site has an API. The honest answer: search demand exists, but the product does not. The closest match for what those developers actually want is a feature-rich developer API like Astrology API.
