EmailEngine vs OpenSend
EmailEngine
emailengine.appOpenSend
opensend.namuh.coSide by side
| Figure | EmailEngine | OpenSend |
|---|---|---|
| Price from | $120.83/mo | $10/mo |
| Free plan | — | — |
| Free trial | Yes | — |
| Open source | — | — |
| Web | Yes | Yes |
| Windows | Yes | — |
| macOS | Yes | — |
| Linux | Yes | — |
| API | Yes | Yes |
| Self-hosted | Yes | Yes |
| Plans published | 2 | 5 |
| Spec score · Email APIs | 8.6 (#4) | 7.3 (#25) |
| Product | EmailEngine is a self-hosted email API that connects existing Gmail, Microsoft 365 and IMAP mailboxes through a unified REST API. | OpenSend describes itself as an open email infrastructure platform with a Resend-compatible API, SDK, broadcasts, contacts, and dashboard. |
| Security | Stored mailbox credentials and OAuth2 tokens can be encrypted with AES-256-GCM when the deployment’s EENGINE_SECRET key is configured. | Dashboard and API routes are tenant-scoped through Better Auth organizations and server-side ownership checks. |
| Support | The maker says support goes directly to the developer who wrote the code, and its annual subscription includes developer support. | The Free and Lite plans include community support, Starter has email support with a 48-hour response target, and Growth has priority support with a 12-hour target. |
Plans
EmailEngine
- Annual subscription$1,450 a year
- Enterprise perpetual licencePriced on request
OpenSend
- Lite$10 a month
- Starter$19 a month
- Growth$99 a month
- FreePrice not published
- ScalePriced on request
In their own words
EmailEngine
EmailEngine is a self-hosted email API that connects Gmail, Microsoft 365, and IMAP mailboxes through a unified REST API. It sends webhooks when mailbox messages or state change, and can send mail through the connected account’s SMTP server or provider API. Native integrations use the Gmail API and Microsoft Graph; authentication options include managed OAuth2, service accounts for Google Workspace, Microsoft 365 app-only access, and shared or delegated mailboxes. An optional MCP server, currently in beta, lets connected AI clients search, read, file, draft, and send email with approved access. The admin interface shows sync status and queue details, with a Prometheus endpoint and Grafana dashboard for operations. EmailEngine runs on the customer’s infrastructure, uses Redis for sync metadata, and fetches message bodies on demand rather than storing them. A server and Redis using the noeviction policy are required. The annual subscription is $1,450 a year, excluding VAT where applicable, and includes developer support; each installation can start a full-functionality 14-day trial without signup or a credit card.
OpenSend
OpenSend has no write-up on Specifiction yet; its figures are above.