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Circle

Circle Signing API

The Signing API from Circle — 4 operation(s) for signing.

Documentation Provider Profile APIs.io OpenAPI GitHub

Circle Signing API is one of 7 APIs that Circle publishes on the APIs.io network, described by a machine-readable OpenAPI specification.

Tagged areas include Signing. The published artifact set on APIs.io includes an OpenAPI specification and API documentation.

This API exposes 4 operations across 4 paths. It is described by OpenAPI 3.2.0, at version 2026-05-23.

Requests are made against a single base URL, https://api.circle.com.

4 operations 4 paths 0 schemas 4 POST

Metadata

The identity and technical contract details declared by the specification.

Specification
OpenAPI 3.2.0
API Version
2026-05-23
Base URL
https://api.circle.com/v1/w3s
Authentication
HTTP Bearer
Contact
Circle Developer Support
License
Proprietary
Resource Areas
1

Authentication & Security 1

Circle Signing API declares 1 security scheme for authenticating requests. It accepts HTTP bearer tokens (BearerAuth). By default, every request must be authenticated.

  • BearerAuth — Circle API key, formatted as PREFIX:ID:SECRET, supplied as Bearer token.

Paths & Operations 4

Across 4 paths, the API surfaces 4 operations — 4 POST. Each is listed below with its method, path, parameters, and response codes.

Signing 4
POST
/v1/w3s/developer/sign/message
Sign a message
signMessage → 200
POST
/v1/w3s/developer/sign/typedData
Sign EIP-712 typed data
signTypedData → 200
POST
/v1/w3s/developer/sign/transaction
Sign a transaction
signTransaction → 200
POST
/v1/w3s/developer/sign/delegateAction
Sign a delegate action
signDelegateAction → 200

Specification

The full machine-readable OpenAPI contract behind this narrative.

Source

circle-signing-api-openapi.yml Raw ↑

Other APIs Circle publishes across the network.

Gas Station and Paymaster
AE Profile APIs.io
Circle NFTs API
AE Profile APIs.io
Circle Tokens API
AE Profile APIs.io
Circle Transactions API
AE Profile APIs.io
Circle Wallet Sets API
AE Profile APIs.io
Circle Wallets API
AE Profile APIs.io
#Signing
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API Details
ID
circle:circle-signing-api
Base URL
https://api.circle.com/v1/w3s
Docs
https://developers.circle.com/w3s/programmable-wallets
Provider
Circle
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