Research Preview — This API is under development.

Area

Calculate the area of a polygon in square meters.

POST /compute/v0/area

Request body

number

required

Target chain ID (e.g., 84532 for Base Sepolia).

Input

required

The polygon geometry to measure. See Input types for accepted formats.

string

EAS schema UID. The server uses a default schema if not provided.

string

Ethereum address to receive the attestation. Defaults to the zero address.

Example request

curl -X POST https://staging-api.astral.global/compute/v0/area \
  -H "Content-Type: application/json" \
  -H "X-API-Key: your-api-key" \
  -d '{
    "chainId": 84532,
    "geometry": "0xpolygon...",
    "recipient": "0xdef456..."
  }'

const response = await fetch('https://staging-api.astral.global/compute/v0/area', {
  method: 'POST',
  headers: {
    'Content-Type': 'application/json',
    'X-API-Key': 'your-api-key'
  },
  body: JSON.stringify({
    chainId: 84532,
    geometry: '0xpolygon...',
    recipient: '0xdef456...'
  })
});

const result = await response.json();

Response

Returns a NumericComputeResponse.

number

required

Area in square meters (e.g., 5432.10).

string

required

Always "square_meters".

string

required

Always "area".

number

required

Unix timestamp of computation.

string[]

required

Array of input references.

AttestationData

required

Signed EAS attestation. See AttestationData.

DelegatedAttestationData

required

Signature for delegated onchain submission. See DelegatedAttestationData.

Example response

{
  "result": 5432.10,
  "units": "square_meters",
  "operation": "area",
  "timestamp": 1706400000,
  "inputRefs": [
    "0xpolygon..."
  ],
  "attestation": {
    "schema": "0x...",
    "attester": "0x590fdb53ed3f0B52694876d42367192a5336700F",
    "recipient": "0xdef456...",
    "data": "0x...",
    "revocable": true,
    "refUID": "0x0000000000000000000000000000000000000000000000000000000000000000",
    "signature": "0x..."
  },
  "delegatedAttestation": {
    "signature": "0x...",
    "attester": "0x590fdb53ed3f0B52694876d42367192a5336700F",
    "deadline": 1706403600,
    "nonce": 0
  }
}

Notes

Uses PostGIS ST_Area with geodetic calculation
Result is in square meters with square centimeter precision
The onchain attested value is scaled to square centimeters (integer) for EVM compatibility
Only valid for polygon geometries

SDK Method

See astral.compute.area()