What data does Vessels API provide?

Vessels API provides real-time AIS vessel positions, voyage history, port congestion metrics, fleet aggregation, and IMO CII carbon intensity scoring through a single normalized REST API.

What is IMO CII and why does it matter?

CII (Carbon Intensity Indicator) is an IMO regulation (MEPC.339) that rates each vessel A–E based on its carbon emissions per nautical mile sailed. Our /vessels/green endpoint computes the CII score automatically from AIS position data.

How fresh is the AIS position data?

Positions are sourced from AIS satellite and terrestrial feeds and aggregated vessel tracking sources. Position history goes back up to 168 hours via /vessels/track. Real-time premium AIS is available via /vessel/live-position on paid plans.

Is there a free trial?

Yes — all paid plans include a 7-day free trial so you can validate your integration before committing.

What authentication method does the API use?

All requests require an API key sent in the X-API-Key request header. Keys are generated from your dashboard and can be revoked at any time.

Vessels API — Real-time Ship Tracking & Maritime Data

18 endpoints 248+ ports JSON REST API 7-day free trial

18 endpoints · 17 try free below

Everything maritime data in one API

From live AIS position to fleet-wide emissions — one key, one base URL. Premium /vessel/live-position is documented separately.

Vessel Position

Live AIS position by IMO — the starting point for most maritime integrations.

Real-time Tracking

Position history (up to 168h), active route, and recent port calls in one call.

Vessel Search

Find vessels by name before you track them. Paginated catalog for search UIs.

Fleet Management

Up to 100 vessels in one POST. Built for fleet dashboards and enterprise monitoring.

Port Intelligence

Congestion, expected arrivals, and in-port activity — six port endpoints for supply chain visibility.

NEW

CII Emissions Scoring

IMO CII rating (A–E) from AIS data — growing ESG demand. CO₂ tons and g/nm for sustainability reports.

View all 18 endpoints in the docs

Try it now

Test the API on this page

Send real requests against our REST API — no signup required. 17 endpoints available in the demo (everything except /vessel/live-position, premium AIS feed). You get 5 free demo calls per device.

Endpoint

Request

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Response

Start with Vessel position or pick any endpoint above.

Quick start

Integrate in minutes

Get your API key

Add the header

Pass X-API-Key: YOUR_KEY to any request. No OAuth, no tokens.

Parse JSON

Every response follows the same {status, success, data} envelope. Ship on day one.

cii-score.sh

# Get IMO CII emissions rating for any vessel
curl -H "X-API-Key: YOUR_API_KEY" \
  "https://vessels-api.com/api/V1/vessels/green?mmsi=258785000&period=30d"

# Response
{
  "data": {
    "name": "ATLANTIC STAR",
    "distance_nm": 4200,
    "estimated_emissions": {
      "co2_tons": 1850.3,
      "co2_per_nm": 0.44
    },
    "cii": {
      "score": 13.2,
      "rating": "C",
      "regulation_reference": "IMO CII"
    }
  }
}

$166.67/mo · billed annually 2 months free

120,000 requests / month
120 requests / minute
Unlimited API Keys
Everything in Business
1,500 AIS live endpoint / month (official feed)

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Custom plans for teams that outgrow standard tiers — tailored limits, support, and integrations.

Custom volumeTailored API request limits
Priority support24/7 technical assistance
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FAQ

Frequently asked questions

AIS positions are sourced from a network of terrestrial and satellite AIS receivers, enriched with voyage data from multiple maritime data providers. Port data covers 248+ ports worldwide through aggregated port authority and maritime intelligence feeds.

CII (Carbon Intensity Indicator) is an IMO regulation (MEPC.339(76)) that rates vessels A–E based on CO₂ emitted per capacity-mile sailed. Our /vessels/green endpoint computes the score from AIS distance data and vessel type emission factors — no onboard sensors required.

Positions are refreshed continuously. Position history via /vessels/track goes back up to 168 hours (7 days). If a vessel's position is older than our freshness threshold, the API fetches a live scrape automatically.

Any language that can make HTTP requests: Python, Node.js, Go, PHP, Ruby, Java, curl — whatever your stack. No SDK required, responses are plain JSON.

Yes. All paid plans start with a 7-day free trial.

Yes — the /vessels/green endpoint is purpose-built for ESG workflows. It returns CO₂ tons, grams-per-nm, and a formal IMO CII rating (A–E) that you can include directly in sustainability reports.

18 endpoints — free 7-day trial

Your first API call, in under 5 minutes.

Sign up, grab your key, make a request. No OAuth, no SDKs, no sales call. If it doesn't fit your stack, cancel before the trial ends — no charge.

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Cancel anytime JSON responses, any language

The vessel tracking API developers actually use.

Everything maritime data in one API

Vessel Position

Real-time Tracking

Vessel Search

Fleet Management

Port Intelligence

CII Emissions Scoring

Test the API on this page

Integrate in minutes

Get your API key

Add the header

Parse JSON

Simple, transparent pricing

Starter

Basic

Professional

Business

Scale

Need more volume?

Frequently asked questions

Your first API call, in under 5 minutes.

The vessel tracking API
developers
actually use.