Square

API

APIs for online and in-person payments, orders, catalog and inventory

Price: Fee per transaction
Access: Access token

About

Commerce platform with APIs for card payments online and in person, orders, catalog, inventory, customers, invoices and bookings, tied to Square's point of sale. Card processing is only available to sellers in eight countries.

What you can do with it

Take card and wallet payments online with the Web Payments SDK and Payments API
Sync items, prices and stock levels with the Catalog and Inventory APIs
Send invoices, run subscriptions and issue gift cards for Square sellers

Get started

Create an application in the Square Developer Console
Copy its Sandbox access token

Example

curl https://connect.squareupsandbox.com/v2/payments \
  -X POST \
  -H "Square-Version: 2026-09-16" \
  -H "Authorization: Bearer $SQUARE_ACCESS_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"idempotency_key": "7b0f3ec5-086a-4871-8f13-3c81b3875218", "source_id": "cnon:card-nonce-ok", "amount_money": {"amount": 100, "currency": "USD"}}'

Details

Hosting: Hosted service
Available in: Australia, Canada, France, Ireland, Japan, Spain, United Kingdom, United States
Official SDKs: Go, Java, C#, JavaScript/TypeScript, PHP, Python, Ruby
MCP server: Remote