Quickstart

1. Create an API key

1. Sign in to the Seamless backoffice.
2. Go to Settings, then System Settings, and find API keys.
3. Choose Create API key. Give it a name, pick the sites it covers and tick what it can read.
4. Copy the key. It is shown once and cannot be retrieved later.

Keys start with k_live_. A key is as sensitive as a password, so keep it on your server and out of web pages and mobile apps.

2. Make a request

Send a POST with a JSON body containing your query. Replace YOUR_API_KEY with your key.

curl https://api.seamlesspos.com/graphql \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"query": "{ sites { id name currency timezone } }"}'

You get back the sites the key covers:

{
  "data": {
    "sites": [
      {
        "id": "66159dbc4cd289f22a12a7ba",
        "name": "The Harbour Cafe",
        "currency": "GBP",
        "timezone": "Europe/London"
      }
    ]
  }
}

You can also paste your key into the API explorer and run queries from the browser.

3. Read some sales

All data is read through a site. If your key covers one site you can leave the site id out:

{
  site {
    name
    orders(from: "2026-11-01T00:00:00Z", to: "2026-11-02T00:00:00Z") {
      nodes {
        number
        businessDate
        closedAt
        total
        items { name price }
        payments { type amount }
      }
      nextCursor
    }
  }
}

Try it in the explorer

If the key covers several sites, name the one you want: site(id: "66159dbc4cd289f22a12a7ba").

From code

The API needs no client library, so any HTTP client can call it.

Node.js 18 or later

const res = await fetch("https://api.seamlesspos.com/graphql", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.SEAMLESS_API_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    query: `query Orders($from: DateTime!, $to: DateTime!) {
      site { orders(from: $from, to: $to) { nodes { number total } nextCursor } }
    }`,
    variables: { from: "2026-11-01T00:00:00Z", to: "2026-11-02T00:00:00Z" },
  }),
});
const { data, errors } = await res.json();
if (errors) throw new Error(errors[0].message);
console.log(data.site.orders.nodes);

Python

import os, requests

res = requests.post(
    "https://api.seamlesspos.com/graphql",
    headers={"Authorization": f"Bearer {os.environ['SEAMLESS_API_KEY']}"},
    json={
        "query": """query Orders($from: DateTime!, $to: DateTime!) {
          site { orders(from: $from, to: $to) { nodes { number total } nextCursor } }
        }""",
        "variables": {"from": "2026-11-01T00:00:00Z", "to": "2026-11-02T00:00:00Z"},
    },
)
body = res.json()
if body.get("errors"):
    raise RuntimeError(body["errors"][0]["message"])
print(body["data"]["site"]["orders"]["nodes"])

Next

Conventions explains why amounts are in pence and what a business date is. Pagination covers reading more than one page, and orders and refunds describes the sales data in detail.