The Hyvor Relay Insider’s Guide
Everything we know about Hyvor Relay in one document: what it costs, its grades, getting a refund, getting help and what else to look at. Read it here, or keep a copy.
Hyvor Relay
The Insider’s Guide
Open-source email API you can self-host
Every plan, grade, refund rule and rival among email sending services, read from Hyvor Relay’s own pages.
Made by Hyvor · checked Nov 13, 2026 · toolgpa.com
Contents
- 01WelcomeWhat it is, who it suits, its grades and the ten things to know first
- 02What it costsEvery plan, the free plan, ways to pay less and how prices have moved
- 03What it doesIts main features, where it runs, what it works with and who makes it
- 04Where it standsIts grades against its category, and whether to keep it or make your own
- 05The alternativesThe tools it is most often weighed against, side by side
- 06Quick answersThe questions people ask about it, each answered in a line or two
- 07About ToolGPAWho made this guide, what else is on the site, and how to cite it
ToolGPA put this guide together from Hyvor Relay’s own pages, its app-store listings and our grades. Every fact in it is on Hyvor Relay’s page too, where it is kept up to date. Checked Nov 13, 2026.
Part 01 · Overview
Welcome
What it is, who it suits, its grades and the ten things to know first
1.8
GPA, above 4 of the 50 other email sending services we grade
Hyvor Relay is an open-source email API under the AGPL-3.0 license. It offers a REST API with idempotent sends, domain and DKIM management, webhooks, suppression handling and 30 days of delivery logs. It is self-hosted today, with a managed cloud version listed as a waitlist.
To get you started, here are 9 things to know about Hyvor Relay, taken from its own pages and our grades.
Self-hosting means servers, DNS, IP reputation and deliverability are yours to run.
- 1
Best for self-hosted open-source email sending
Hyvor Relay is an open-source email API you run on your own servers, free under AGPL-3.0.
- 2
Paid plans start at about $931 a month
As its pricing page puts it: €10,000 per year and up (Enterprise License).
- 3
There is a free plan
Self-hosted open-source edition: free with unlimited usage under AGPL-3.0 and community support.
- 4
It runs on Web
Web.
- 5
Email API
A REST API with idempotent sends, HTML and plain text, attachments, custom headers and multiple recipients.
- 6
Domains and DKIM
Multiple sending domains with enforced DKIM signing and an in-built DNS server.
- 7
Webhooks
Event webhooks for deliveries, bounces and domain verification.
- 8
A 1.8 GPA, above 4 of 50
That is against the other email sending services we grade, on value, the free plan, features, ease of use and platforms.
- 9
Keep it
To replace Hyvor Relay you would be making mail servers with a good name among inbox providers. That is not a weekend's work, with an AI app builder or without one.
Hyvor Relay at a glance
- Pricing
- Free plan, from €10,000 per year and up (Enterprise License)
- Free plan
- Yes
- Free trial
- None stated
- Runs on
- Web
- Made by
- Hyvor
- Category
- Email Sending Services
- Our grade
- 1.8 GPA, weak
The report card
Best for self-hosted open-source email sending
Hyvor Relay is an open-source email API you run on your own servers, free under AGPL-3.0. A hosted cloud plan is only a waitlist with an estimate of €30 a month, so for now you either run servers and deal with delivery yourself or pay from €10,000 a year.
| Subject | Grade | Comment |
|---|---|---|
| Value for money | C | Free only if you host it yourself, which needs servers and IPs, so it sits in the middle. The Enterprise License starts at €10,000 a year, and the cloud plan is an unconfirmed estimate. |
| Free plan and trial | C | The open-source edition is free with unlimited usage, but you must run it yourself, and there is no hosted free tier. |
| Features | C | Email API, DKIM domains, webhooks, bounce and complaint handling, projects and observability. Delivery logs last 30 days. |
| Ease of use | D | No rating on record. Self-hosting means servers, DNS, IP reputation and deliverability are yours to run. |
| Platforms and integrations | C | Web interface and API, with Prometheus, Grafana and Docker Swarm hooks. No apps. |
An A is worth 4 points, a B 3, a C 2, a D 1 and an F nothing. The GPA is the average of the five.
Who Hyvor Relay is for
- Fits if you can run your own mail servers and want no per-email fee
- Works for teams that need the open-source license for compliance
Who it is not for
- Skip it if you do not run servers, as self-hosting leaves deliverability to you
- Watch out: the hosted cloud plan is a waitlist and its €30 a month is an estimate, not final
- Pricey if you need to avoid the AGPL-3.0, since the Enterprise License starts at €10,000 a year
- Tight if you need long logs, with delivery logs kept for 30 days
Good to know
Good for
- Teams that want to run their own sending infrastructure
- Organizations that need a commercial license instead of AGPL-3.0
Worth knowing
- The cloud plan is on a waitlist, listed at an estimated €30 per month for 300,000 emails and not yet final.
- Self-hosting means running servers, IPs and deliverability yourself.
- Delivery logs are kept for 30 days.
- The page states the Enterprise License starts at €10,000 a year and is priced by volume.
Part 02 · Pricing
What it costs
Every plan, the free plan, ways to pay less and how prices have moved
~$931
A month to start. There is a free plan too
Hyvor Relay has a free plan. Paid plans start at €10,000 per year and up (Enterprise License).
Free only if you host it yourself, which needs servers and IPs, so it sits in the middle.
Self-Hosted Open-Source
$0
You host it yourself under AGPL-3.0, with all features and community support.
Enterprise License
€10,000
per year and up
The same features without AGPL-3.0 obligations, with volume-based pricing, enterprise support and SLA options.
The free plan
Self-hosted open-source edition: free with unlimited usage under AGPL-3.0 and community support.
Read from relay.hyvor.com on Nov 13, 2026.
Part 03 · Features
What it does
Its main features, where it runs, what it works with and who makes it
1
Place it runs: Web
Open-source email API you can self-host. Here is what it does, as its own site describes it, and what it covers: open source, self-hostable, public API, transactional email.
Email API, DKIM domains, webhooks, bounce and complaint handling, projects and observability.
- Email API
- A REST API with idempotent sends, HTML and plain text, attachments, custom headers and multiple recipients.
- Domains and DKIM
- Multiple sending domains with enforced DKIM signing and an in-built DNS server.
- Webhooks
- Event webhooks for deliveries, bounces and domain verification.
- Bounce and complaint handling
- Bounces, complaints and suppressions are managed automatically.
- Projects
- Isolated projects each with their own domains, keys and webhooks.
- Observability
- Prometheus and Grafana integrations and health checks for servers, DNS and IP reputation.
Where it runs
- Web
What it works with
- Prometheus
- Grafana
- Docker Swarm
Hyvor Relay is made by Hyvor.
Part 04 · Standing
Where it stands
Its grades against its category, and whether to keep it or make your own
4/50
Other email sending services it is graded above
Hyvor Relay's GPA of 1.8 is higher than 4 of the 50 other email sending services we grade, and level with 4.
It stands best on free plan and trial (C, above 11 of 50) and worst on ease of use (D, above 0).
Its paid plans start at about $931 a month, against a middle price of $15 for the category: 41 of the 41 others that charge start lower.
On features, ease of use and platforms it scores 1.7 out of 4. 41 tools score higher and cost less.
Each grade against the category
Every bar is all 51 email sending services we grade, cut by the letter each got. Hyvor Relay’s own letter is outlined.
- CValue for moneyAbove 8 of 50
- CFree plan and trialAbove 11 of 50
- CFeaturesAbove 0 of 50
- DEase of useAbove 0 of 50
- CPlatforms and integrationsAbove 0 of 50
Price against what you get
Each dot is one of 44 email sending services. Further left costs less; higher up scores better on features, ease of use and platforms. Hyvor Relay is the marked dot.
What paid plans start at, a month (each step along is roughly double) →
Keep it, or make your own?
Whether this is something you could build for yourself with an AI app builder, and what you would give up.
Keep it
To replace Hyvor Relay you would be making mail servers with a good name among inbox providers. That is not a weekend's work, with an AI app builder or without one.
That makes this kind of software worth paying for, not this one in particular: 42 of the 50 other email sending services grade higher. It costs $11,172 a year. Hyvor Relay is open source, so there is a third way: take its code and run it yourself.
What you could not
- Mail servers with a good name among inbox providers.
- It plugs into other products, Prometheus, Grafana and Docker Swarm among them, and has an API.
What this rests on. Hyvor Relay’s listing: what it does, where it runs, what it plugs into and what it costs. It is a judgement about the kind of software this is. We have not built a replacement for it, and making your own means looking after it too. How we decide, and every tool’s verdict.
Part 05 · Alternatives
The alternatives
The tools it is most often weighed against, side by side
Plunk, Postmark, Mailgun, Amazon SES and KumoMTA
The 5 tools Hyvor Relay is most often weighed against, with where each one differs from it.
- 2.6GPA
Plunk
Free plan · from $0.001
Open-source email platform for transactional and marketing mail.
- Plunk also covers workflow automation and email campaigns.
- 2.2GPA
Postmark
Free plan · from $15/mo
Transactional email API and SMTP, with broadcasts on a separate stream.
- Hyvor Relay is open source and self-hostable, according to its own site.
- Postmark also covers dMARC.
- 2.4GPA
Mailgun
Free plan · from $15/mo
Email API and SMTP relay for developers, with list validation.
- Hyvor Relay is open source and self-hostable, according to its own site.
- Mailgun also covers email verification.
- 2.8GPA
Amazon SES
Free trial
AWS email sending and receiving, paid per 1,000 emails.
- Hyvor Relay has a free plan. Amazon SES does not, though it has a free trial.
- Hyvor Relay is open source and self-hostable, according to its own site.
- Amazon SES also covers email verification.
- 2.2GPA
KumoMTA
Free plan · from $5,000/yr
Open-source mail server for high-volume, self-run email sending.
- Only Hyvor Relay lists a web app.
- Only KumoMTA lists a Linux app.
Part 06 · Questions
Quick answers
The questions people ask about it, each answered in a line or two
13
Questions, each answered in a line or two
The short version of everything above, for when you only need the answer. Each one is told in full in its part of the guide.
Is Hyvor Relay free?
Hyvor Relay has a free plan. Self-hosted open-source edition: free with unlimited usage under AGPL-3.0 and community support.
How much does Hyvor Relay cost?
Hyvor Relay lists 2 plans. Self-Hosted Open-Source: $0.
What platforms does Hyvor Relay work on?
Hyvor Relay is available on Web.
Does Hyvor Relay have an Android app?
No Android app was listed when its pages were read on Nov 13, 2026. Hyvor Relay is listed for Web.
Does Hyvor Relay have an iPhone app?
No iPhone app was listed when its pages were read on Nov 13, 2026. Hyvor Relay is listed for Web.
Is Hyvor Relay open source?
Yes. Hyvor Relay is open source, according to its own site.
Does Hyvor Relay have an API?
Yes. Hyvor Relay offers a public API, according to its own site.
What does Hyvor Relay integrate with?
Hyvor Relay's listing names Prometheus, Grafana and Docker Swarm. A listing names up to eight integrations, so it may connect to more.
Who makes Hyvor Relay?
Hyvor Relay is made by Hyvor.
What are the alternatives to Hyvor Relay?
The closest alternatives to Hyvor Relay in our directory are Plunk, Postmark, Mailgun, Amazon SES and KumoMTA.
How does Hyvor Relay compare with other email sending services?
Hyvor Relay's GPA of 1.8 is higher than 4 of the 50 other email sending services we grade, and level with 4.
Is Hyvor Relay good value for money?
ToolGPA grades Hyvor Relay C for value for money. Its paid plans start at about $931 a month, against a middle price of $15 for the category: 41 of the 41 others that charge start lower.
Could I make my own version of Hyvor Relay?
To replace Hyvor Relay you would be making mail servers with a good name among inbox providers.
Where this guide comes from
The prices, plans, platforms and features were read from Hyvor Relay’s own pages on Nov 13, 2026, and the grades were given on Nov 13, 2026. Graded from this listing, whose facts were read from Hyvor's own pages on 13 November 2026. Not based on using the product, and shorter than our full reviews.
Every tool we list gets five grades, A to F, each with its reason, and a GPA that averages them. How each is decided is at toolgpa.com/grades. This guide is ToolGPA’s own work; it is not made, paid for or approved by Hyvor. Prices change, so check relay.hyvor.com before you buy.
Part 07 · About
About ToolGPA
Who made this guide, what else is on the site, and how to cite it
7,721
Tools graded, in 95 categories
ToolGPA grades software the way a school report grades a pupil: five subjects, a letter for each with the reason written beside it, and a GPA that averages them. Prices, plans and platforms are read from each maker’s own pages and dated, so you always know how fresh a figure is.
Every grade, review and ranking on ToolGPA is our own judgement. No company can pay for a grade or change one. Every tool on the site has a guide like this one, free to download and pass on. It all lives at toolgpa.com.
7,721
tools graded
95
categories
739
price changes on record
579
apps priced in 12 countries
What else is on toolgpa.com
- Hyvor Relay, kept up to dateEverything in this guide, with prices and grades as they are todaytoolgpa.com/tools/hyvor-relay
- How grades are givenThe rules behind every letter and every GPAtoolgpa.com/grades
- Value chartsWhat each tool costs against what it scores, for every categorytoolgpa.com/charts
- CompareAny two tools side by side, plan by plantoolgpa.com/compare
- Price changesEvery price rise and cut on record, each with its sourcetoolgpa.com/price-changes
- Prices by countryWhat apps cost on the App Store in 12 countriestoolgpa.com/prices-by-country
- Pay lessEvery public discount: yearly billing, students, nonprofitstoolgpa.com/save
- Keep or makeWhich tools are worth paying for, and which you could build yourselftoolgpa.com/keep-or-make
Scan for the live page
Prices and grades as they are today
Quoting this guide?
Please name ToolGPA and link to the live page, so readers can check the figures for themselves:
ToolGPA, "Hyvor Relay: The Insider's Guide", checked Nov 13, 2026. https://toolgpa.com/tools/hyvor-relay
Know someone choosing between email sending services?
Send them this guide: toolgpa.com/tools/hyvor-relay/guide
ToolGPA elsewhere: youtube.com/@toolgpa
See our other guides
The best-graded email sending services after Hyvor Relay, each with an Insider's Guide of its own.
- Email Sending Services Insider's GuideEvery one of the 51 email sending services we grade, compared
- FluentSMTP Insider's GuideFree WordPress plugin for sending site email through your provider3.2 GPA
- Amazon SES Insider's GuideAWS email sending and receiving, paid per 1,000 emails2.8 GPA
- Forward Email Insider's GuideOpen-source email forwarding and hosting for custom domains2.8 GPA
Choosing software? Every tool graded, every price dated.
Compare tools at toolgpa.com ›Everything in this guide is ToolGPA’s own summary of what Hyvor Relay’s pages, its app-store listings and public reviews said on the dates shown. Grades are our judgement under the rules at toolgpa.com/grades. Every grade, review and ranking on ToolGPA is our own judgement. No company can pay for a grade or change one. Hyvor Relay is a trademark of its owner, and this guide is not made, paid for or approved by Hyvor. Prices and plans change: check relay.hyvor.com before you buy.