#36 in Collaboration & CommunicationUpdated 2026-08

Hyvor Relay

by Hyvor Relay · Open-source, self-hosted email API for developers

42.7 — BenchRank score out of 100

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Pricing page

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Overview

Hyvor Relay is an email sending service you run on your own infrastructure, offering a REST API for sending mail plus scope-based APIs for domains, suppressions, API keys and webhooks. It signs mail with DKIM, runs an integrated DNS server for MX, SPF and DKIM records, handles bounces and complaints, and scales horizontally with Docker Swarm.

Best for: Developers who want to self-host a transactional email API instead of using SES, Mailgun or SendGrid.
Pricing: Self-hosting is free under AGPL-3.0; an enterprise licence starts at €10,000/year, and the not-yet-launched Cloud plan is estimated at €30/month for 300,000 emails plus €1 per extra 10,000.
Runs on: Self-hosted

Strengths and trade-offs

Strengths

Open-source under AGPL-3.0, with all features in the free build
Built-in DNS server handles MX, SPF and DKIM records
Delivery logs with headers, status and SMTP traces for 30 days
Prometheus and Grafana integrations for monitoring

Trade-offs

AGPL-3.0 obligations unless you buy a licence from €10,000/year
Hosted Cloud is waitlist-only, planned for Q1 2026 at estimated prices
No built-in login or signup: an OIDC provider is required
No newsletter or marketing email features; Hyvor Post is a separate product

Pricing

Published plans from Hyvor Relay’s own pricing page, in USD. Usage charges and add-ons may apply on top.

Hyvor Relay pricing tiers, monthly rates in USD
Plan	Monthly	Includes
Self-Hosted Open-Source	—	Free forever, unlimited usage All features included AGPL-3.0 obligations apply Community support
Enterprise License	Contact sales	Tailored pricing starting at €10,000/year No AGPL-3.0 obligations Volume-based pricing and enterprise support SLA options
Cloud Standard	€30per month, 300,000 emails included	€1 per additional 10,000 emails Priority support and managed deliverability SLA and uptime guarantee Waitlist only; pricing marked as estimated

How this score is made up

Each dimension is scored out of 100 and combined into the headline score using fixed weights.

MCP support: 0 out of 100
API quality: 20 out of 100
Documentation: 80 out of 100
Agent friendliness: 62 out of 100
Changelog: 80 out of 100
Marketing site structure: 60 out of 100
Operational trust: 25 out of 100

Measured, but not part of the score

Useful to know, but not a mark for or against the product — so these do not affect the ranking.

Openness: 65 out of 100
Maintenance: 100 out of 100

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