Audience
AI agent builders that need an email API for AI agents
About Sendmux
Sendmux gives AI agents their own inbox and a controlled way to send email. Each agent can receive messages, read threads, handle attachments, send replies, and react to new mail through signed webhooks or Server-Sent Events.
Teams can send through Gmail OAuth, Outlook OAuth, SMTP providers, or managed Amazon SES. Sendmux can spread sending across providers with weighted routing, sender-domain routing, health checks, failover, and quotas by second, minute, hour, or day.
Developers get Mailbox, Sending, and Management APIs, OpenAPI docs, SDKs, the sendmux CLI, MCP tools, and Sendmux Skills. The platform also covers tenant isolation, mailbox-scoped API keys, custom domains, logs, metrics, and usage-based pricing with no per-seat or per-mailbox fees.
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Pricing
Starting Price:
$0.15 per 1000 emails
Free Version:
Free Version available.
Company Information
Sendmux
Founded: 2026
Australia
sendmux.ai
Videos and Screen Captures
Unified Inbox
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Product Details
Platforms Supported
Cloud
Training
Documentation
Live Online
In Person
Videos
Support
Phone Support
24/7 Live Support
Online
Sendmux Frequently Asked Questions
Q: What kinds of users and organization types does Sendmux work with?
Sendmux works with these users and organization types: Mid Size Business, Small Business, Enterprise, Freelance, Nonprofit, Government, and Startup.
Q: What languages does Sendmux support in their product?
Sendmux supports these languages: English.
Q: What kind of support options does Sendmux offer?
Sendmux offers support via phone support, 24/7 live support, and online.
Q: What other applications or services does Sendmux integrate with?
Sendmux integrates with: Vercel AI SDK, Claude Duet, Claude for Legal, Claude, Codex CLI, FetchSandbox, Gmail, LangChain, Microsoft Outlook, Model Context Protocol (MCP), n8n, Python, Ruby, Slack, and Zapier.
Q: Does Sendmux have an API?
Yes, Sendmux has an API.
Q: What type of training does Sendmux provide?
Sendmux provides training in the form of documentation, live online, in person, and videos.
Q: How much does Sendmux cost?
Pricing for Sendmux starts at $0.15 per 1000 emails.
