Earn
Earn.com (formerly 21 Inc / 21.co) was a cryptocurrency startup that let people earn Bitcoin by replying to paid messages and completing microtasks, effectively a paid-email and paid-task marketplace settled in crypto. Founded by Balaji Srinivasan and backed by DCVC among others, the company was acquired by Coinbase in April 2018 (Coinbase, ticker COIN) and folded into the Coinbase Earn product. The independent earn.com property no longer operates a standalone product or developer surface: earn.com now issues a 301 redirect to coinbase.com/earn, and earlier hosts such as 21.co and api.earn.com no longer resolve. This profile is retained in the API Evangelist network as an acquired-company record; there is no independent, first-party API, developer portal, or OpenAPI to enrich.
Index entry only — little beyond a description and a link, and nothing machine-readable enough for an agent to act on without a human reading the site first.
API Evangelist profiles Earn the way a machine reads it — 1 machine-readable artifact, pulled from the provider's own public surface and indexed so a developer, an analyst, or an AI agent can evaluate it against every other provider on the network.
Every provider in the network is reduced to the same set of machine-readable artifacts — OpenAPI contracts, event specifications, GraphQL schemas, runnable collections, pricing and rate-limit signals, security posture, OAuth scopes, and the agent surfaces (MCP servers and skills) that let software drive the API on its own. We profile them because the interface is the part of a company you can actually inspect: it is a truer signal of what a provider does than any marketing page. From those artifacts we compute the Kin Score — Earn scores 7.7/100 (minimal), with a separate agent-readiness read of 0/100 (human only). The full breakdown is below, followed by every artifact we hold — each card links through to its machine-readable definition on apis.io.
Kin Score
This is the API Evangelist rating — a single, repeatable read computed from the artifacts on this page. Green fill is points earned; the red track is points possible, so every bar shows earned-versus-possible at a glance.
Kin Score
How this is scored →scored 2026-07-27 · rubric v0.5
How we profile Earn
Each block below is one kind of artifact we hold for Earn. For each we say what it is and why it earns a place in the profile, then list every one we've indexed — capped at two rows, scroll within the panel for the rest.
Security Posture 1
Authentication, domain security, vulnerability disclosure, and trust-center signals — the evidence that a provider takes security seriously enough to document it. We profile it because you can't govern what you can't see.
Authentication, domain security, vulnerability disclosure, and trust-center signals.
Resources
Every other property we hold for Earn — documentation, portals, status pages, policies, and corporate surface — grouped by the job it does, following the integrator's arc from getting started to running in production.
Access & Security 1
Authentication, authorization, and security posture
Company 1
The organization behind the API
← All providers · Data indexed from github.com/api-evangelist/earn · machine-readable index on apis.io