The EmailEngine Insider’s Guide
Everything we know about EmailEngine 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.
EmailEngine
The Insider’s Guide
Self-hosted REST API for Gmail, Microsoft 365 and IMAP mailboxes
Every plan, grade, refund rule and rival among email sending services, read from EmailEngine’s own pages.
Made by Postal Systems OÜ · 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 EmailEngine’s own pages, its app-store listings and our grades. Every fact in it is on EmailEngine’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
1.6
GPA, above 1 of the 50 other email sending services we grade
EmailEngine is software you run on your own server that turns Gmail, Microsoft 365 and IMAP accounts into a REST API, with webhooks for incoming mail and a send endpoint. It is built by the author of Nodemailer. One flat subscription covers unlimited mailboxes, instances and API calls.
To get you started, here are 9 things to know about EmailEngine, taken from its own pages and our grades.
You host it yourself and it needs a Redis database that keeps its data.
- 1
Best for a REST API over Gmail, Microsoft 365 and IMAP
EmailEngine is software you run on your own server that turns Gmail, Microsoft 365 and IMAP mailboxes into a REST API with webhooks.
- 2
Paid plans start at $120.83 a month when paid by the year
As its pricing page puts it: $199 per month, or $1,450 per year (€169 or €1,200).
- 3
You can try it first
14-day free trial, no sign-up or credit card, activated on your own server
- 4
It runs on Web
Web.
- 5
One REST API for three mailbox types
Read, send and sync Gmail, Microsoft 365 and generic IMAP accounts through the same API.
- 6
Webhooks for incoming mail
New messages in a connected mailbox are pushed to your application as parsed JSON, so the app does not poll or speak IMAP.
- 7
Managed OAuth2
Handles OAuth2 for Microsoft 365 and Google Workspace, and can bridge legacy apps that only speak IMAP and SMTP.
- 8
A 1.6 GPA, above 1 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 EmailEngine 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.
EmailEngine at a glance
- Pricing
- Free trial, from $199 per month, or $1,450 per year (€169 or €1,200)
- Free plan
- No
- Free trial
- 14-day free trial, no sign-up or credit card, activated on your own server
- Runs on
- Web
- Made by
- Postal Systems OÜ
- Category
- Email Sending Services
- Our grade
- 1.6 GPA, weak
The report card
Best for a REST API over Gmail, Microsoft 365 and IMAP
EmailEngine is software you run on your own server that turns Gmail, Microsoft 365 and IMAP mailboxes into a REST API with webhooks. It's one flat price, $1,450 a year, and you need Redis and your own server to run it.
| Subject | Grade | Comment |
|---|---|---|
| Value for money | D | $1,450 a year, or $199 a month, whatever the mailbox count. That's about $121 a month on yearly billing, above the category's dearest tenth at $68. |
| Free plan and trial | C | 14-day free trial, no sign-up and no card, started on your own server. After that it needs a subscription. |
| Features | C | One REST API for three mailbox types, webhooks for incoming mail, managed OAuth2 and a send endpoint. It's a mailbox API, not a sending service. |
| Ease of use | D | No store rating on record. You host it yourself and it needs a Redis database that keeps its data. |
| Platforms and integrations | C | Runs on Linux, macOS, Windows and Docker as a program on your own machine, with no hosted version. It connects to Gmail, Microsoft 365 and Google Workspace. |
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 EmailEngine is for
- Fits if you're building an app that has to read and send from your users' own mailboxes
- Works for teams with many mailboxes who want one flat price and can run a server
Who it is not for
- Skip it if you want a hosted service, because you run it yourself and there isn't one
- Pricey if you have only a few mailboxes, as the price is the same $1,450 a year for any number
- Not for you if you want open source: it's source available and needs a subscription past the trial
- Watch out: it needs a Redis database that persists data
- Watch out: prices leave out VAT
Good to know
Good for
- SaaS products and CRMs that sync or send from their users' own mailboxes
- Regulated teams that need to control where mailbox data is processed
- Developers who want one API instead of separate Gmail, Graph and IMAP code
Worth knowing
- It is source available rather than open source: running it beyond the trial requires a subscription.
- You host it yourself and it needs a Redis database that must persist data.
- The flat price is $1,450 a year ($199 a month) whatever the mailbox count, so it suits larger use more than a few mailboxes.
- Prices exclude VAT, and the vendor lists the product's platforms as Linux, macOS, Windows and Docker with no hosted version.
Part 02 · Pricing
What it costs
Every plan, the free plan, ways to pay less and how prices have moved
$120.83
A month to start, paid by the year
EmailEngine is a paid product with a free trial, starting at $199 per month, or $1,450 per year (€169 or €1,200).
Subscription
$1,450
per year, unlimited mailboxes ($199 billed monthly)
Unlimited mailboxes, instances, API calls, webhooks and licence keys, plus updates while subscribed. In euros: €1,200 a year or €169 a month; VAT extra.
Enterprise
Custom
The same software with a perpetual licence paid once, offline verification, invoice or wire payment, net terms and custom contract terms.
Trying it first
14-day free trial, no sign-up or credit card, activated on your own server
Read from emailengine.app 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
Self-hosted REST API for Gmail, Microsoft 365 and IMAP mailboxes. Here is what it does, as its own site describes it, and what it covers: self-hostable, public API, transactional email.
It's a mailbox API, not a sending service.
- One REST API for three mailbox types
- Read, send and sync Gmail, Microsoft 365 and generic IMAP accounts through the same API.
- Webhooks for incoming mail
- New messages in a connected mailbox are pushed to your application as parsed JSON, so the app does not poll or speak IMAP.
- Managed OAuth2
- Handles OAuth2 for Microsoft 365 and Google Workspace, and can bridge legacy apps that only speak IMAP and SMTP.
- Self-hosted deployment
- Ships as a single binary, a Docker image, an npm package and an installer script, and needs a Redis database.
- Agent access
- The same API is offered as a tool surface for AI agents that read, summarize, draft and send mail.
Where it runs
- Web
What it works with
- Gmail
- Microsoft 365
- Google Workspace
EmailEngine is made by Postal Systems OÜ.
Part 04 · Standing
Where it stands
Its grades against its category, and whether to keep it or make your own
1/50
Other email sending services it is graded above
EmailEngine's GPA of 1.6 is higher than 1 of the 50 other email sending services we grade, and level with 2.
It stands best on free plan and trial (C, above 11 of 50) and worst on value for money (D, above 0).
Its paid plans start at $120.83 a month when paid by the year, against a middle price of $15 for the category: 38 of the 41 others that charge start lower.
On features, ease of use and platforms it scores 1.7 out of 4. 39 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. EmailEngine’s own letter is outlined.
- DValue for moneyAbove 0 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. EmailEngine 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 EmailEngine 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: 47 of the 50 other email sending services grade higher. It costs $1,450 a year.
What you could not
- Mail servers with a good name among inbox providers.
- It plugs into other products, Gmail, Microsoft 365 and Google Workspace among them, and has an API.
What this rests on. EmailEngine’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
Nodemailer, Forward Email, Mailgun, Postmark and Twilio SendGrid
The 5 tools EmailEngine is most often weighed against, with where each one differs from it.
- 2.6GPA
Nodemailer
Free
Free Node.js library for sending email over SMTP and other transports.
- Nodemailer has a free plan. EmailEngine does not, though it has a free trial.
- EmailEngine is self-hostable, according to its own site.
- Nodemailer is open source, according to its own site.
- 2.8GPA
Forward Email
Free plan · from $3/mo
Open-source email forwarding and hosting for custom domains.
- Forward Email has a free plan. EmailEngine does not, though it has a free trial.
- Only Forward Email lists macOS, Windows, Linux, iOS and Android apps.
- Forward Email is open source, according to its own site.
- 2.4GPA
Mailgun
Free plan · from $15/mo
Email API and SMTP relay for developers, with list validation.
- Mailgun has a free plan. EmailEngine does not, though it has a free trial.
- EmailEngine is self-hostable, according to its own site.
- Mailgun also covers email verification.
- 2.2GPA
Postmark
Free plan · from $15/mo
Transactional email API and SMTP, with broadcasts on a separate stream.
- Postmark has a free plan. EmailEngine does not, though it has a free trial.
- EmailEngine is self-hostable, according to its own site.
- Postmark also covers dMARC.
- 2.6GPA
Twilio SendGrid
Free trial · from $19.95/mo
Twilio's email API and SMTP service, priced by monthly email volume.
- EmailEngine is self-hostable, according to its own site.
- Twilio SendGrid also covers email verification.
Part 06 · Questions
Quick answers
The questions people ask about it, each answered in a line or two
14
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 EmailEngine free?
No, EmailEngine is a paid product, but you can try it first. 14-day free trial, no sign-up or credit card, activated on your own server.
How much does EmailEngine cost?
EmailEngine lists 2 plans. Subscription: $1,450 per year, unlimited mailboxes ($199 billed monthly).
What platforms does EmailEngine work on?
EmailEngine is available on Web.
Does EmailEngine have an Android app?
No Android app was listed when its pages were read on Nov 13, 2026. EmailEngine is listed for Web.
Does EmailEngine have an iPhone app?
No iPhone app was listed when its pages were read on Nov 13, 2026. EmailEngine is listed for Web.
Is EmailEngine open source?
EmailEngine is not described as open source on its own site, as read on Nov 13, 2026.
Can EmailEngine be self-hosted?
Yes. EmailEngine's own site says it can be run on a server of your own.
Does EmailEngine have an API?
Yes. EmailEngine offers a public API, according to its own site.
What does EmailEngine integrate with?
EmailEngine's listing names Gmail, Microsoft 365 and Google Workspace.
Who makes EmailEngine?
EmailEngine is made by Postal Systems OÜ.
What are the alternatives to EmailEngine?
The closest alternatives to EmailEngine in our directory are Nodemailer, Forward Email, Mailgun, Postmark and Twilio SendGrid.
How does EmailEngine compare with other email sending services?
EmailEngine's GPA of 1.6 is higher than 1 of the 50 other email sending services we grade, and level with 2.
Is EmailEngine good value for money?
ToolGPA grades EmailEngine D for value for money. Its paid plans start at $120.83 a month when paid by the year, against a middle price of $15 for the category: 38 of the 41 others that charge start lower.
Could I make my own version of EmailEngine?
To replace EmailEngine 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 EmailEngine’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 EmailEngine'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 Postal Systems OÜ. Prices change, so check emailengine.app 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
- EmailEngine, kept up to dateEverything in this guide, with prices and grades as they are todaytoolgpa.com/tools/emailengine
- 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, "EmailEngine: The Insider's Guide", checked Nov 13, 2026. https://toolgpa.com/tools/emailengine
Know someone choosing between email sending services?
Send them this guide: toolgpa.com/tools/emailengine/guide
ToolGPA elsewhere: youtube.com/@toolgpa
See our other guides
The best-graded email sending services after EmailEngine, 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 EmailEngine’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. EmailEngine is a trademark of its owner, and this guide is not made, paid for or approved by Postal Systems OÜ. Prices and plans change: check emailengine.app before you buy.