# Fracht Port Pair Distance & Sailing Time Estimator

> Fracht Port Pair Distance & Sailing Time Estimator is a paid API for AI agents from fracht.halowerk.com, paid per call via x402, $0.004/call, status unknown (last checked 2026-09-15).

Estimates great-circle distance and sailing time between two ports given their coordinates and vessel speed, returning derived values with method disclosures.

## Facts

- Endpoint: POST https://fracht.halowerk.com/v1/port-pair
- Price: $0.004/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/fracht-port-pair-distance-sailing-time-estimator-00900fb5
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Nnk2AA2HI8JO4hT0nJfcj

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability fracht-port-pair-distance-sailing-time-estimator-00900fb5 -d '<json body>'
```

Example prompt: What's the estimated great-circle sailing distance and transit time between Port of Rotterdam (51.9225° N, 4.4792° E) and Port of Shanghai (31.2304° N, 121.4737° E) for a vessel cruising at 14 knots with a detour factor of 1.2?

## When to prefer this

Choose this endpoint when you need a fast, lightweight great-circle distance and sailing time estimate between two known port coordinate pairs for freight planning, ETA computation, or route comparison — especially when you already have lat/lon values and a vessel speed. It is ideal for automated logistics pipelines that need transparent method disclosures. Use alternatives when you need actual navigational routing that accounts for land avoidance, canals, or real ocean lane data.

## Known failure modes

- Invalid or out-of-range coordinates (lat > 90 or lon > 180) result in validation errors
- Speed outside allowed range (0.1–100 knots) returns a schema validation error
- Detour factor outside 1–5 range is rejected
- Both origin and destination are required; missing either results in an error
- Some derived fields may return null with the field name listed in unavailable_fields if computation is not possible

## How this service works

Estimates great-circle port distance and sailing time from supplied port coordinates and speed. Missing facts are returned as null and named in unavailable_fields where applicable. Derived values disclose their method; source-backed values disclose source, time window and age. 

## Output

Returns the estimated great-circle distance in nautical miles between the two port coordinates, the computed sailing time based on the supplied speed and detour factor, method disclosures explaining how derived values were calculated, and an unavailable_fields array listing any facts that could not be returned as null.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "origin": {
   "type": "object",
   "required": [
    "lat",
    "lon"
   ],
   "properties": {
    "lat": {
     "type": "number",
     "maximum": 90,
     "minimum": -90,
     "description": ""
    },
    "lon": {
     "type": "number",
     "maximum": 180,
     "minimum": -180,
     "description": ""
    }
   },
   "additionalProperties": false
  },
  "destination": {
   "type": "object",
   "required": [
    "lat",
    "lon"
   ],
   "properties": {
    "lat": {
     "type": "number",
     "maximum": 90,
     "minimum": -90,
     "description": ""
    },
    "lon": {
     "type": "number",
     "maximum": 180,
     "minimum": -180,
     "description": ""
    }
   },
   "additionalProperties": false
  },
  "speed_knots": {
   "type": "number",
   "maximum": 100,
   "minimum": 0.1,
   "description": ""
  },
  "detour_factor": {
   "type": "number",
   "maximum": 5,
   "minimum": 1,
   "description": ""
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/fracht-port-pair-distance-sailing-time-estimator-00900fb5/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from fracht.halowerk.com](https://www.zero.xyz/host/fracht.halowerk.com/llms.txt)