Developers

Chart data, without the account flow.

The PathFinder Public API provides deterministic natal, transit, and sky calculations from the same engine used in the app. Read the calculation methodology and the published accuracy benchmark for its conventions and test coverage.

OpenAPI 3.1 document ↗

Quickstart

Three endpoints, no API key.

Send JSON to the public origin. All date-time fields are local wall-clock values: no UTC offset and no Z suffix. Pair each one with an IANA time-zone ID.

POST/v1/charts/natal

Get planets, houses, angles, aspects, and calculation metadata for a birth chart.

curl -sS -X POST "https://public-api.pathfindercharts.com/v1/charts/natal" \
  -H "Content-Type: application/json" \
  -H "X-Request-Id: natal-rotterdam-001" \
  -d '{
    "birthDateTime": "1990-06-15T14:42:00",
    "latitude": 51.9244,
    "longitude": 4.4777,
    "timezoneId": "Europe/Amsterdam",
    "cityName": "Rotterdam",
    "countryCode": "NL"
  }'

POST/v1/charts/transits

Get a bi-wheel with natal and transit positions plus cross-aspects. A real birth block is required.

curl -sS -X POST "https://public-api.pathfindercharts.com/v1/charts/transits" \
  -H "Content-Type: application/json" \
  -H "X-Request-Id: transits-rotterdam-001" \
  -d '{
    "birthDateTime": "1990-06-15T14:42:00",
    "latitude": 51.9244,
    "longitude": 4.4777,
    "timezoneId": "Europe/Amsterdam",
    "transitDateTime": "2026-08-28T12:00:00",
    "transitTimezoneId": "Europe/Amsterdam"
  }'

POST/v1/charts/sky

Get a single-wheel geocentric sky with planets and aspects. Add latitude and longitude when you also need houses and angles.

curl -sS -X POST "https://public-api.pathfindercharts.com/v1/charts/sky" \
  -H "Content-Type: application/json" \
  -H "X-Request-Id: sky-amsterdam-001" \
  -d '{
    "transitDateTime": "2026-08-28T12:00:00",
    "transitTimezoneId": "Europe/Amsterdam"
  }'

Anonymous access

A small public allowance.

The three quickstart operations accept requests without a key: natal, transits, and sky. They allow 5 requests per minute and 10 successful data responses per day, per observed public IP address. For IPv6, the identity is the observed /64.

Successful data responses consume the daily allowance. Check the response headers before scheduling or retrying work.

Errors and retries

Problems have a stable shape.

Errors use application/problem+json following RFC 9457, with a machine-stable errorCode, retry guidance, and a suggestion. A 429 includes Retry-After; wait for that period before retrying.

HTTP/1.1 429 Too Many Requests
Content-Type: application/problem+json
Retry-After: 12

{
  "type": "https://public-api.pathfindercharts.com/problems/rate_limited",
  "title": "Rate limited",
  "status": 429,
  "errorCode": "rate_limited",
  "retryable": true,
  "retryAfterSeconds": 12,
  "suggestion": "Per-minute limit hit; back off retryAfterSeconds."
}

Response headers

Know what remains.

Header	Meaning
`X-RateLimit-Limit`	Maximum requests admitted in the current minute.
`X-RateLimit-Remaining`	Requests still available in that rate-limit window.
`X-RateLimit-Reset`	Seconds until the current rate-limit window resets.
`X-Quota-Remaining`	Successful data responses remaining in the current UTC-day quota.
`X-Request-Id`	Request correlation ID. Supply one to support idempotent retries; it is echoed on metered responses, not on rate-limit rejections.
`Retry-After`	Seconds to wait before retrying a 429 rate-limit or quota response.

API keys

Use a key for the full surface.

Keyed access tiers cover synastry, archetype profiles, calendar events, and chart render creation. Send the key in X-API-Key. Render creation can return an expiring signed image URL; fetching that URL needs no key. Higher limits and full endpoint access are available with an API key on request. Contact PathFinder to discuss access; there is no self-serve key signup.