Loop Crypto

Loop Crypto is a crypto and stablecoin payment processor that lets merchants, billing software, and e-commerce platforms accept crypto and stablecoin payments end to end: charging a wallet, storing payment methods, accepting stablecoins, ERC-20 tokens, and Solana SPL tokens, and settling to merchants in either fiat or crypto. Loop offers payment links, an embeddable Pay/PayIn checkout component, a white-labelable Connect widget, and a REST API (v1/v2, api-key + entity-id header auth) covering customers, entities, merchants, tokens, payments, payouts, and webhooks, plus out-of-the-box integrations with Stripe, Chargebee, and OpenPay. Backed by a16z. NOTE: Loop is winding down and folding into Lead; the service was sunset on 2026-02-13 and is not recommended for new integrations.

Loop Crypto publishes 1 API on the APIs.io network. Tagged areas include Company, Payments, Cryptocurrency, Stablecoins, and Web3.

The Loop Crypto catalog on APIs.io includes 1 event-driven AsyncAPI specification.

Loop Crypto’s developer surface includes documentation, API reference, getting-started guide, signup flow, engineering blog, authentication, sandbox, and 12 more developer resources.

🌐 Visit website 📡 Source on GitHub
32.6/100 thin ▬ flat Agent 15/100 agent aware Full breakdown ↓
scored 2026-07-27 · rubric v0.5
AccessSelf serve
1 APIs
CompanyPaymentsCryptocurrencyStablecoinsWeb3Payment ProcessingBillingSolanaEthereum

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-07-27 · rubric v0.5
Composite quality — 32.6/100 · thin
Contract Quality 5.7 / 25
Developer Ergonomics 13.5 / 20
Commercial Clarity 2.6 / 20
Operational Transparency 2.7 / 13
Governance 0.0 / 12
Discoverability 9.3 / 10
Agent readiness — 15/100 · agent aware
Machine-Readable Contract 0 / 18
Agentic Access Contract 0 / 15
MCP Server 0 / 12
Machine-Readable Auth 10 / 10
Idempotency 0 / 9
Stable Error Semantics 0 / 8
Request/Response Examples 0 / 7
Rate-Limit Signaling 0 / 7
Typed Event Surface 6 / 6
Agent Skills 0 / 5
Well-Known Catalog 0 / 4
Consent & Bot Identity 0 / 3
Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. This rating is computed from github.com/api-evangelist/loop-crypto: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

APIs 1

Individual APIs this provider publishes, each with its own machine-readable definition.

Loop Crypto API

REST API for accepting crypto and stablecoin payments — customers, entities, merchants, tokens, payments, payouts, and webhooks. Authenticated with api-key and entity-id headers...

Event Specifications 1

AsyncAPI definitions for this provider's event-driven and streaming APIs.

Loop Crypto Webhooks

ASYNCAPI

Security Posture 2

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Loop Crypto Authentication

apiKey · 2 schemes

SECURITY

Loop Crypto Domain Security

DNSSEC · DMARC

SECURITY

Resources

Get Started 4

Portal, sign-up, and the first successful call

DeveloperPortal
DeveloperPortal
 GettingStarted
GettingStarted
 SignUp
SignUp
 Sandbox
Sandbox

Documentation 2

Reference material describing how the API behaves

Documentation
Documentation
 APIReference
APIReference

Agent Surfaces 1

MCP servers, agent skills, and machine-readable catalogs

LLMsTxt
LLMsTxt

Design & Contract 4

Pagination, idempotency, versioning, errors, and events

Conventions
Conventions
 Webhooks
Webhooks
 Lifecycle
Lifecycle
 Components
Components

Build 4

SDKs, sample code, and the tooling you integrate with

GitHubOrganization
GitHubOrganization
 Packages
Packages
 SDKs
SDKs
 CLI
CLI

Access & Security 2

Authentication, authorization, and security posture

Authentication
Authentication
 DomainSecurity
DomainSecurity

Operate 1

Status, limits, changes, and where to get help

Deprecation
Deprecation

Company 1

The organization behind the API

Blog
Blog

Source (apis.yml)

apis.yml Raw ↑ 
aid: loop-crypto
accessModel:
  pricing: unknown
  onboarding: self-serve
  trial: false
  try_now: false
  public: false
  label: Self-serve signup
  confidence: medium
  source:
  - authentication
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/loop-crypto.png
name: Loop Crypto
description: 'Loop Crypto is a crypto and stablecoin payment processor that lets merchants, billing software, and e-commerce
  platforms accept crypto and stablecoin payments end to end: charging a wallet, storing payment methods, accepting stablecoins,
  ERC-20 tokens, and Solana SPL tokens, and settling to merchants in either fiat or crypto. Loop offers payment links, an
  embeddable Pay/PayIn checkout component, a white-labelable Connect widget, and a REST API (v1/v2, api-key + entity-id header
  auth) covering customers, entities, merchants, tokens, payments, payouts, and webhooks, plus out-of-the-box integrations
  with Stripe, Chargebee, and OpenPay. Backed by a16z. NOTE: Loop is winding down and folding into Lead; the service was sunset
  on 2026-02-13 and is not recommended for new integrations.'
url: https://raw.githubusercontent.com/api-evangelist/loop-crypto/refs/heads/main/apis.yml
x-type: company
x-source: vc-portfolio
x-backed-by:
- a16z
x-tier: stub
x-tier-reason: portfolio-lead
x-status: sunset
x-sunset-date: '2026-02-13'
x-successor: Lead
specificationVersion: '0.20'
created: '2026-07-17'
modified: '2026-07-20'
tags:
- Company
- Payments
- Cryptocurrency
- Stablecoins
- Web3
- Payment Processing
- Billing
- Solana
- Ethereum
apis:
- name: Loop Crypto API
  description: REST API for accepting crypto and stablecoin payments — customers, entities, merchants, tokens, payments, payouts,
    and webhooks. Authenticated with api-key and entity-id headers; URI-path versioned (v1, v2). A demo environment is available
    at demo.api.loopcrypto.xyz.
  humanURL: https://docs.loopcrypto.xyz
  baseURL: https://api.loopcrypto.xyz/api/v2/
  properties:
  - type: Documentation
    url: https://docs.loopcrypto.xyz
  - type: APIReference
    url: https://docs.loopcrypto.xyz/api/webhooks/list-webhooks
  - type: Authentication
    url: authentication/loop-crypto-authentication.yml
  - type: Webhooks
    url: asyncapi/loop-crypto-webhooks.yml
common:
- type: DeveloperPortal
  url: https://docs.loopcrypto.xyz
- type: Documentation
  url: https://docs.loopcrypto.xyz
- type: APIReference
  url: https://www.loopcrypto.xyz/api
- type: GettingStarted
  url: https://docs.loopcrypto.xyz/docs/get-set-up
- type: SignUp
  url: https://www.loopcrypto.xyz/get-started
- type: Blog
  url: https://www.loopcrypto.xyz/blog
- type: GitHubOrganization
  url: https://github.com/LoopCrypto
- type: Authentication
  url: authentication/loop-crypto-authentication.yml
- type: Conventions
  url: conventions/loop-crypto-conventions.yml
- type: Webhooks
  url: asyncapi/loop-crypto-webhooks.yml
- type: Lifecycle
  url: lifecycle/loop-crypto-lifecycle.yml
- type: Deprecation
  url: lifecycle/loop-crypto-lifecycle.yml
- type: Sandbox
  url: sandbox/loop-crypto-sandbox.yml
- type: Packages
  url: packages/loop-crypto-packages.yml
- type: SDKs
  url: packages/loop-crypto-packages.yml
- type: CLI
  url: cli/loop-crypto-cli.yml
- type: Components
  url: components/loop-crypto-components.yml
- type: DomainSecurity
  url: security/loop-crypto-domain-security.yml
- type: LLMsTxt
  url: llms/loop-crypto-llms.txt
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
x-enrichment:
  date: '2026-07-20'
  status: enriched
  artifacts_added: 10
  pass: local-v1