EmptyInbox vs Mailinator

EmptyInbox provides disposable email inboxes for AI agents and developers through a REST API, an MCP server and a web inbox. A new address can be created for each task or agent run. Messages can be polled, or received through the MCP wait_for_message flow, which can extract verification codes. The web inbox uses passkey sign-in and displays extracted codes and links alongside messages. Each inbox creation uses one credit; receiving, listing and reading messages are free. Messages are deleted automatically after seven days. EmptyInbox receives email only and has no sending endpoint or SMTP credentials. Listed integrations include MCP-compatible agents, OpenAI GPT Actions, LangChain, CrewAI and OpenAPI-compatible frameworks; workflow guides cover Playwright, Cypress, n8n and LangChain. The free plan includes five inbox credits and REST API and MCP access. One-time top-ups start at 1.00 USD for 10 credits, payable by Bitcoin or USDT. The project is open source under the MIT license, and questions go through GitHub issues.

Mailinator provides temporary inboxes and tools for testing email and SMS workflows. Developers, QA teams, and businesses can use it to check delivery for OTP, MFA, onboarding, password recovery, and other email processes at scale. Paid subscriptions include private testing domains, where messages can arrive at any address without creating an inbox first. The REST API retrieves inboxes, messages, and SMS, injects messages, and connects with CI/CD pipelines. Inbound webhooks can accept HTTP POST messages from sources such as alert systems, Zapier, or Twilio, then apply configured rules. SMS can be routed to an inbox or API for automated OTP and 2FA testing. The free public inboxes are readable by anyone, and messages typically auto-delete after several hours. Mailinator is receive-only: it cannot send email or fill out forms. The Public - Free plan is free to use without sign-up. Business costs $79 a month billed yearly; a two-week Business trial is listed. Other plans include Verified Pro at free, Business Plus at $159 a month billed yearly, and Enterprise at a price agreed with the maker with custom pricing.