Deliver high-converting welcome emails the second users sign up with zero spam folder landing
First impressions matter. Send verified, DKIM-signed onboarding emails, activation sequences, and product tour guides with low-latency API latency and dedicated deliverability warm-up.
Drop into your application in under 60 seconds
Native typed interfaces with zero unnecessary dependencies. Built for standard fetch and modern edge runtimes.
import { SadaSend } from 'sadasend';
const sadasend = new SadaSend(process.env.SADASEND_API_KEY);
export async function sendWelcomeEmail(user: { email: string; name: string }) {
return await sadasend.emails.send({
from: 'Sarah from SadaSend <welcome@yourdomain.com>',
to: user.email,
subject: `Welcome to the team, ${user.name}!`,
html: `
<div style="font-family: sans-serif; max-width: 600px; margin: 0 auto;">
<h2>Welcome aboard, ${user.name}!</h2>
<p>Your workspace is live. Here are 3 quick steps to get started:</p>
<ol>
<li>Complete your workspace profile</li>
<li>Invite your team members</li>
<li>Create your first project</li>
</ol>
<p><a href="https://yourdomain.com/dashboard" style="background: #0284c7; color: white; padding: 10px 20px; text-decoration: none; border-radius: 6px;">Go to Dashboard</a></p>
</div>
`,
});
}Dispatch personalized onboarding welcome emails with instant edge latency and automated open/click tracking telemetry.
Engineered for high deliverability and zero incident risk
Every layer from edge connection pooling to per-key rate limits is designed to keep critical transactional dispatches fast, reliable, and contained.
low-latency Dispatch Latency
Ensure welcome emails hit the user inbox while they are still looking at your signup success screen, maximizing conversion rates.
100% DKIM, SPF & DMARC Alignment
Every email is signed with your custom domain keys to bypass Gmail and Apple Mail promotional/spam filtering algorithms.
Built-In Open & Click Telemetry
Track onboarding engagement with real-time webhooks streaming to your analytics platform or product event bus.
Dynamic Template Variables
Easily inject dynamic recipient names, invitation links, workspace tokens, and custom CTA paths into clean HTML templates.
Pre-Warmed IP Infrastructure
High sender reputation pool prevents new SaaS domains from suffering throttling delays during sudden launch spikes.
6,000 Free Monthly Emails
Scale your user onboarding from day one with custom domain authentication and analytics completely free.
SadaSend vs Traditional Marketing ESPs (Mailchimp / Brevo)
Why product engineering teams use SadaSend transactional API instead of bulk marketing newsletter software for welcome sequences.
| Feature & Capability | SadaSend | Traditional Marketing ESPs (Mailchimp / Brevo) |
|---|---|---|
| Delivery Delay / Queue Lag | Accepted on the API call, then queued | 5 to 45 minute batch processing delay |
| Custom DKIM Domain Signing | Included on 100% of accounts | Locked behind high-cost enterprise plans |
| Synchronous API Response Contract | ||
| Real-Time Event Webhook Stream | Delayed or batched CSV logs | |
| AI Agent & MCP Tool Calling | ||
| Permanent Free Tier | 6,000 sends forever | Limited trial or 300/day hard cap |
Start with 3,000 emails every month at zero cost
No artificial paywalls on security. Unlike legacy providers that reserve recipient allowlists or dedicated IP pools for high enterprise tiers, every SadaSend account receives full safety controls from day one.
Everything you need to know about welcome email API
Clear, transparent answers on deliverability, API authentication, and rate limits.
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