Shift4 · Authentication Profile

Shift4 Authentication

Authentication

Shift4 secures its APIs with apiKey and http across 2 declared security schemes, as derived from its OpenAPI definitions.

PaymentsUnited StatesPayment ProcessingPayment GatewayAcquiringPayment TerminalTokenizationACH3D SecureGift CardsPayment LinksCard Present
Methods: apiKey, http Schemes: 2 OAuth flows: API key in: header

Security Schemes

AccessToken apiKey
· in: header (AccessToken)
HMAC-SHA256 http
scheme: hmac-sha256

Source

Authentication Profile

Raw ↑ 
generated: '2026-07-24'
method: derived
source: openapi/shift4-payment-api.yml
summary:
  types:
  - apiKey
  - http
  api_key_in:
  - header
schemes:
- name: AccessToken
  type: apiKey
  in: header
  parameter: AccessToken
  description: "A security credential used to authenticate API requests and all [i4Go®](https://s4-myportal.s3.amazonaws.com/downloads/documentation/i4go/i4go%20technical%20reference%20guide.pdf)\
    \ authorizeClient/preauthorizeClient requests. An Access Token is the alias for the merchant\
    \ account and interface being used. \n\nExample:\n  ```\n  AccessToken: EA79FB05-3AA7-4500-AF9A-73F986FF2C1D\n\
    \  ```"
  sources:
  - openapi/shift4-payment-api.yml
- name: HMAC-SHA256
  type: http
  scheme: hmac-sha256
  description: "Authentication using HMAC-256 signatures as the authorization scheme.\n\nSent\
    \ in the `Authorization` header in the following format:\n\n`Authorization`: **HMAC-SHA256**\
    \ `Credential`={value}&`Signature`={value}\n\n| Argument      | Description            \
    \                          |\n|---------------|--------------------------------------------------|\n\
    | HMAC-SHA256   | Authorization scheme.                "
  sources:
  - openapi/shift4-payment-api.yml

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