Resend

About Resend

Resend is a modern email API built for developers. It offers excellent developer experience and reliable deliverability.

Website: resend.com

Prerequisites

1. A Resend account
2. A verified domain (or use Resend’s test domain)
3. An API key with send permissions

Getting Your API Key

1. Log in to Resend
2. Go to API Keys in the sidebar
3. Click Create API Key
4. Give it a name (e.g., “mailshit production”)
5. Select Full access or Sending access
6. Copy the key (starts with re_)

Configuration

Add Resend in mailshit:

1. Go to Settings > Providers
2. Click Add Provider
3. Select Resend
4. Enter the following:

5. Click Save

Domain Verification

For production use, verify your domain in Resend:

1. Go to Domains in Resend dashboard
2. Click Add Domain
3. Add the DNS records Resend provides
4. Wait for verification (usually minutes)

Without a verified domain, you can only send to your own email address.

Free Tier

Resend offers a generous free tier:

• 3,000 emails/month
• 100 emails/day
• 1 custom domain
• Up to 1 year of email logs

Example Flow

[Variables] → [Template] → [Resend Output]

When the flow executes with a Resend output:

{
  "success": true,
  "type": "sent",
  "messageId": "re_msg_123..."
}

Best Practices

1. Verify your domain for better deliverability
2. Use a subdomain like mail.yourdomain.com for transactional email
3. Set up DKIM through Resend’s domain verification
4. Monitor bounce rates in Resend’s dashboard

Troubleshooting

“Sender not verified”

• Verify your domain in Resend
• Or use Resend’s onboarding email address for testing

“Rate limit exceeded”

• Free tier: 100 emails/day
• Wait or upgrade your Resend plan

“Invalid API key”

• Check the key starts with re_
• Regenerate the key in Resend’s dashboard