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.

Earn is profiled on the APIs.io network. Tagged areas include Company, Cryptocurrency, Bitcoin, Payments, and Acquired.

🌐 Visit website 📡 Source on GitHub

7.7/100 minimal ▬ flat Agent 0/100 human only Full breakdown ↓
scored 2026-07-27 · rubric v0.5

0 APIs

CompanyCryptocurrencyBitcoinPaymentsAcquiredCoinbase

Kin Score

Kin Score How this is scored →
scored 2026-07-27 · rubric v0.5

Composite quality — 7.7/100 · minimal

Contract Quality 0.0 / 25

Developer Ergonomics 0.0 / 20

Commercial Clarity 0.0 / 20

Operational Transparency 0.0 / 13

Governance 0.0 / 12

Discoverability 6.8 / 10

Agent readiness — 0/100 · human only

Machine-Readable Contract 0 / 18

Agentic Access Contract 0 / 15

MCP Server 0 / 12

Machine-Readable Auth 0 / 10

Idempotency 0 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 0 / 7

Typed Event Surface 0 / 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/earn: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

Access & Security 1

Authentication, authorization, and security posture

DomainSecurity

DomainSecurity

Company 1

The organization behind the API

Website

Website

Source (apis.yml)

aid: earn
name: Earn
description: '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.'
url: https://raw.githubusercontent.com/api-evangelist/earn/refs/heads/main/apis.yml
x-type: company
x-source: vc-portfolio
x-backed-by:
- dcvc
x-tier: stub
x-tier-reason: portfolio-lead
x-status: acquired
x-acquired-by: coinbase
x-acquired-year: '2018'
x-former-names:
- 21 Inc
- 21.co
accessModel:
  pricing: unknown
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Unknown
  confidence: low
  source: []
  generated: '2026-07-22'
  method: derived
specificationVersion: '0.20'
created: '2026-07-17'
modified: '2026-07-18'
tags:
- Company
- Cryptocurrency
- Bitcoin
- Payments
- Acquired
- Coinbase
image: https://raw.githubusercontent.com/api-evangelist/earn/refs/heads/main/apis.yml
apis: []
common:
- type: DomainSecurity
  url: security/earn-domain-security.yml
- type: Website
  url: https://earn.com
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
x-enrichment:
  date: '2026-07-19'
  status: backfilled
  pass: local-v1
  note: backfilled from .gitignore signal + verified work evidence

Earn

Kin Score

Security Posture 1

Earn Domain Security

Resources

Access & Security 1

Company 1

Source (apis.yml)