One API. Every channel.

send-email.ts
send0.emails.send("Welcome to Acme");
Validation:PASSED
Routing:OPTIMIZED
Compliance:CHECKED
Email
WhatsApp
SMS

Send email, WhatsApp, and SMS from a single integration. send0 handles routing, compliance, and infrastructure so you ship faster.

Explore docsGet Started
$npm install send0

Every channel, one integration.

Deep integrations for every messaging channel. Same API, same SDK, same dashboard.

Email

Transactional and marketing email with deliverability, templates, and real-time tracking built in.

Learn more →

WhatsApp

WhatsApp Business API with template management, rich media, and automatic SMS fallback.

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SMS

Global SMS delivery with carrier routing, 10DLC compliance, and two-way messaging.

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Infrastructure, not just an API.

Replace provider fragmentation with a single integration layer that handles routing, deliverability, and compliance across every channel.

Channel Routing

DA

Daniel A.

+1 (914) 123-4567

WhatsAppActive
SMSAvailable
EmailVerified
Selected channelWhatsApp (primary)
Automatic fallback: SMS → Email

Message Lifecycle

08:21:14
ReceivedAPI call validated
08:21:14
QueuedPriority: transactional
08:21:15
SentChannel handshake complete
08:22:29
DeliveredDelivery confirmed
msg_abc123def456Delivered via WhatsApp

The problem with legacy messaging

You want to ship features. Instead, you're managing pipes.

Fragmented Providers

Separate APIs for each channel and carrier. More integrations, more maintenance.

Compliance Overhead

10DLC, WhatsApp templates, opt-out rules — each channel has its own requirements.

Content Transformation

Rich media on WhatsApp, plain text fallback on SMS. You build the logic.

Cost Inefficiency

Without channel-aware routing, you default to the most expensive channel for every message.

How it works

Routing and delivery, handled for you.

Integrate the SDK

Install the package and start sending across channels with a single function call.

$npm install send0
// Send a message
send0.messages.send({
channel: "auto",
to: "+1 (555) 012-3456",
body: "Your order is ready for pickup."
});

Configure Channels

Connect your providers once. send0 manages authentication, credentials, and failover.

Email DomainsSPF / DKIM verified
Active
WhatsApp BusinessConnected
Active
SMS10DLC Registered
Active

Unified Templates

Write once, deliver everywhere. One template renders across all channels automatically.

Template: order_ready
Hi {{name}}, your order {{order_id}} is ready.
WhatsAppHi Jane, your order #4821 is ready.
SMSHi Jane, your order #4821 is ready.
EmailHi Jane, your order #4821 is ready.

Track Everything

Unified event stream across channels. Real-time delivery tracking with HMAC-signed webhooks.

12:00:01queuedmsg_9f2a1c
12:00:02sentmsg_9f2a1c
12:00:04deliveredmsg_9f2a1c
12:01:23readmsg_9f2a1c
WhatsApp · +1 (555) 012-3456Recipient read message

Lower email costs

Usage-based pricing sends emails at the most cost-effective rates. No per-contact fees. Typical savings: 30–40%.

Better deliverability

Automatic domain authentication, reputation monitoring, and suppression management. Your emails reach the inbox.

Ship faster

One integration replaces multiple email providers. Spend time on your product, not email infrastructure.

Pricing

Pay per email sent. No per-contact fees, no hidden charges. Start free and scale as you grow.

Free

$0/ forever

Perfect for getting started and testing your integration.

Start building
  • 3,000 emails per month
  • 1 sending domain
  • Full API access
  • Email events & webhooks
  • Community support
  • Test mode

Pro

$0.40/ per 1,000 emails

Usage-based pricing for growing products. Pay only for what you send.

Start building
  • Unlimited emails
  • Unlimited domains
  • Transactional + marketing
  • Priority queue routing
  • Advanced analytics
  • Template engine
  • Suppression management
  • Email support

Enterprise

Custom

Dedicated infrastructure, custom SLAs, and hands-on onboarding.

Contact sales
  • Everything in Pro
  • Dedicated IP addresses
  • Custom SLAs (99.99%)
  • Volume discounts
  • 24/7 priority support
  • SOC 2 report access

FAQ

send0 is an email infrastructure API for developers. Send transactional and marketing emails through a single integration. We handle deliverability, compliance, and infrastructure.

send0 is built from the ground up as email infrastructure, not just an API wrapper. We own the full delivery stack — from queue management to SMTP infrastructure — which means better deliverability, lower latency, and transparent pricing.

send0 automatically maintains suppression lists. If an address has previously hard-bounced or filed a spam complaint, we suppress the send and log a ‘suppressed’ event. This protects your sender reputation without any manual intervention.

The free tier includes 3,000 emails per month with one sending domain. Full API access including webhooks, events, and test mode. No credit card required.

No. send0 handles all SMTP infrastructure, IP rotation, warm-up, and reputation management. You send via our API, we handle delivery.

Email authentication (SPF, DKIM, DMARC), suppression list enforcement, CAN-SPAM compliance, and GDPR data handling are all built into the platform. Compliance checks happen automatically before every send.

Currently email — both transactional and marketing. WhatsApp and SMS are on the roadmap. The API is designed so adding channels won’t require changing your integration.

Typical end-to-end delivery is under 200ms from API call to SMTP handshake. Transactional emails are always prioritized over marketing sends.