Mailgun

Mailgun

Sinch's email API with detailed analytics, webhooks, and a generous free trial. Region-aware (US or EU).

Easy~5 minAPIUS / EU regions

Prerequisites

• A Mailgun account. New accounts get 5,000 free emails for 30 days.
• A domain you can edit DNS records for (Mailgun's free sandbox domain only sends to verified addresses).

Step-by-step

Add and verify your domain

Mailgun dashboard → Sending → Domains → Add New Domain.

Pick a region (US or EU — they're separate, fully isolated infrastructures) and enter your domain.

Mailgun gives you a list of DNS records to add: TXT (SPF), TXT (DKIM), optionally CNAME (tracking) and MX records.

Add them at your DNS provider (Cloudflare / Route 53 / GoDaddy / etc) and click Verify DNS Settings in Mailgun. Wait 5-30 min for propagation.

Get your API key

Mailgun → Send → Sending → Domain settings → API security.

Copy your Private API Key. It's also at Settings → API Keys in the top-right user menu.

Add the connection in SendGrail

WordPress admin → SendGrail → Connections → Add Connection → pick Mailgun.

Fill in:

• Connection Name: Mailgun
• Domain: your verified domain (e.g. mg.yoursite.com)
• Region: US or EU — must match where you registered the domain
• From Email: an address on the verified domain
• From Name: display name
• API Key: paste the private API key

Click Save.

Test

SendGrail → Test Email → pick the Mailgun connection → send.

Troubleshooting

Domain not found: yourdomain.com

The domain isn't verified in the region you selected. Double-check the region (US vs EU) — they share the same dashboard but are separate APIs. A domain verified in EU won't work via the US endpoint.

Forbidden

API key is wrong or your account is suspended. Regenerate the key in Mailgun → API Keys.

Emails hit the sandbox limit

Mailgun sandbox domains (the default sandbox*.mailgun.org) only send to verified recipient addresses. Add a real domain in step 1 to send to anyone.

Free trial expired

After 30 days, the free trial ends and unsigned accounts are limited to verified recipients. Add a payment method to keep sending freely.

What's next

• Email Routing — route different email types through Mailgun's analytics-rich pipeline.
• Open / Click Tracking — Mailgun has its own tracking; SendGrail's tracking is independent and works on top.