> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://esendex.ferndocs.com/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://esendex.ferndocs.com/_mcp/server.

# Esendex API Dev Portal

> Send SMS, RCS and email, verify users with one-time passcodes, and react to delivery events in real time with the Esendex API.

Esendex API Dev Portal

Connect with customers on every channel through one API.

Send SMS, RCS and email, verify users with one-time passcodes, and react to delivery events in real time — all from a single REST API.

[Get started <path d="M5 12h14" /><path d="m13 6 6 6-6 6" />](/quickstart)

[<path d="m8 7-5 5 5 5" /><path d="m16 7 5 5-5 5" /><path d="m14 4-4 16" />Explore the API ](/api-reference)

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Search the documentation…

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Ask AI

Get started

## Send your first message in minutes.

[Get your API key <path d="m9 6 6 6-6 6" />](/authentication)

[Send your first message <path d="m9 6 6 6-6 6" />](/quickstart)

[Track delivery <path d="m9 6 6 6-6 6" />](/webhooks)

One API, every channel

## Reach customers wherever they are.

[<path d="M21 15a2 2 0 0 1-2 2H7l-4 4V5a2 2 0 0 1 2-2h14a2 2 0 0 1 2 2z" />](/api-reference/messages/send-message)

### SMS

Send one-off or bulk messages with templates and personalisation variables.

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[<rect x="3" y="4" width="18" height="16" rx="2" /><path d="M3 10h18" /><path d="M8 15h3" />](/api-reference/messages/send-message)

### RCS

Deliver rich, branded conversations with media, cards and suggested replies.

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[<rect x="3" y="5" width="18" height="14" rx="2" /><path d="m3 7 9 6 9-6" />](/api-reference/emails/send-email-v-2)

### Email

Send transactional email and track its delivery status.

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[<path d="M12 3 4 6v6c0 5 3.5 8 8 9 4.5-1 8-4 8-9V6z" /><path d="m9 12 2 2 4-4" />](/one-time-passcodes)

### One-time passcodes

Request and verify OTPs for sign-in and two-factor flows.

→