Your data in.
A beautiful PDF out.

curl https://api.castpdf.com/v1/pdf \
  -H "Authorization: Bearer $CASTPDF_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: invoice-INV-2026-0142" \
  -d '{
    "template_id": "8d1f2c3b-4a5e-4f60-9b7a-1c2d3e4f5a6b",
    "data": { "customer": { "name": "Brightwater Coffee Co. Ltd" } },
    "response": "url"
  }'

const res = await fetch('https://api.castpdf.com/v1/pdf', {
  method: 'POST',
  headers: {
    Authorization: `Bearer ${process.env.CASTPDF_API_KEY}`,
    'Content-Type': 'application/json',
    'Idempotency-Key': 'invoice-INV-2026-0142',
  },
  body: JSON.stringify({
    template_id: '8d1f2c3b-4a5e-4f60-9b7a-1c2d3e4f5a6b',
    data: { customer: { name: 'Brightwater Coffee Co. Ltd' } },
    response: 'url',
  }),
});
const { url, expires_at } = await res.json();

import os, requests

res = requests.post(
    "https://api.castpdf.com/v1/pdf",
    headers={
        "Authorization": f"Bearer {os.environ['CASTPDF_API_KEY']}",
        "Idempotency-Key": "invoice-INV-2026-0142",
    },
    json={
        "template_id": "8d1f2c3b-4a5e-4f60-9b7a-1c2d3e4f5a6b",
        "data": {"customer": {"name": "Brightwater Coffee Co. Ltd"}},
        "response": "url",
    },
    timeout=60,
)
print(res.json()["url"])

<?php
$client = new GuzzleHttp\Client(['timeout' => 75]);

$response = $client->post('https://api.castpdf.com/v1/pdf', [
    'headers' => [
        'Authorization' => 'Bearer ' . getenv('CASTPDF_API_KEY'),
        'Idempotency-Key' => 'invoice-INV-2026-0142',
    ],
    'json' => [
        'template_id' => '8d1f2c3b-4a5e-4f60-9b7a-1c2d3e4f5a6b',
        'data' => ['customer' => ['name' => 'Brightwater Coffee Co. Ltd']],
        'response' => 'url',
    ],
]);
echo json_decode((string) $response->getBody())->url;