Email Deliverability

What is this?

Email deliverability is whether your emails actually reach the inbox vs. going to spam or being silently dropped. It depends on three DNS records working together:

• SPF - lists which servers are allowed to send as your domain
• DKIM - cryptographically signs each email to prove it's genuine
• DMARC - enforces what happens when email fails SPF/DKIM, and provides reporting

All three are DNS TXT records - no code changes required, just DNS configuration.

Why it matters

Missing email authentication affects every email you send: account verification, password resets, receipts, support replies. When these land in spam, users think your product is broken. Many churn silently without ever telling you.

Since 2024, Gmail and Yahoo require all three for bulk senders and use them as signals even for low-volume domains.

How to fix it

1. Check what you're missing: run a scan at didyouship.com or check mxtoolbox.com/emailhealth.aspx
2. Add SPF first: TXT record at your root domain
3. Add DKIM: enable in your email provider dashboard, add the DNS record they give you
4. Add DMARC: TXT record at _dmarc.yourdomain.com with p=quarantine
5. Use a reputable transactional email service for all automated email

Providers & tools

Recommended sending services:

• Resend - modern API, great DX, free tier includes 3,000 emails/month
• Postmark - best-in-class deliverability, 100 free emails/month
• SendGrid - 100 free/day, scales to millions
• Brevo (formerly Sendinblue) - 300 free/day, good EU option