The Smtp.dev Insider’s Guide
Everything we know about Smtp.dev 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.
Smtp.dev
The Insider’s Guide
Email testing sandbox with SMTP, IMAP and a REST API
Every plan, grade, refund rule and rival among email sending services, read from Smtp.dev’s own pages.
Made by SMTP Labs, Inc. · 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 Smtp.dev’s own pages, its app-store listings and our grades. Every fact in it is on Smtp.dev’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
2.6
GPA, above 34 of the 50 other email sending services we grade
Smtp.dev is an email testing service for developers. An app or test suite sends mail over SMTP to a sandbox address, and the message can be read back through IMAP, POP3 or the REST API, with headers, MIME structure and raw source. Mail only goes to accounts inside the sandbox, never to real inboxes.
To get you started, here are 9 things to know about Smtp.dev, taken from its own pages and our grades.
You point your app or test suite at it and set DNS records for your own domain.
- 1
Best for testing app email without sending to real inboxes
Smtp.dev is a sandbox where your app sends mail over SMTP and you read it back through IMAP, POP3 or an API.
- 2
Paid plans start at $7 a month
As its pricing page puts it: $7 per month for Pro.
- 3
There is a free plan
Lite plan: 1 domain, 50 accounts, messages kept 7 days, with SMTP, IMAP, POP3, API and email audit.
- 4
It runs on Web
Web.
- 5
SMTP, IMAP and POP3 access
Standard mail clients and libraries connect with ordinary settings, with no SDK to install.
- 6
REST API
Accounts, messages, domains and tokens can be managed over the API, which is limited to 4096 requests a minute per user.
- 7
Message inspection
Shows headers, the MIME tree and the raw RFC 5322 source of each message, plus an HTML preview.
- 8
A 2.6 GPA, above 34 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
Nothing Smtp.dev does is plain enough to make in a weekend. The 2 things listed below take a company.
Smtp.dev at a glance
- Pricing
- Free plan, from $7 per month for Pro
- Free plan
- Yes
- Free trial
- None stated
- Runs on
- Web
- Made by
- SMTP Labs, Inc.
- Category
- Email Sending Services
- Our grade
- 2.6 GPA, good
The report card
Best for testing app email without sending to real inboxes
Smtp.dev is a sandbox where your app sends mail over SMTP and you read it back through IMAP, POP3 or an API. Nothing reaches a real inbox on any plan, and the free Lite plan keeps messages for only 7 days.
| Subject | Grade | Comment |
|---|---|---|
| Value for money | B | Pro is $7 a month, inside the cheapest quarter of email sending tools, which start at $9. Max is $20. |
| Free plan and trial | B | Lite is free: 1 domain, 50 accounts and 7 days of messages, with SMTP, IMAP, POP3, API and email audit. One project could live on that. |
| Features | C | SMTP, IMAP, POP3 and REST API access, message inspection, own-domain receiving and a deliverability audit. It does the testing job fully, but it never sends real email. |
| Ease of use | C | No store rating on record. You point your app or test suite at it and set DNS records for your own domain. |
| Platforms and integrations | B | Web with an API, plus CI use with GitHub Actions, Jenkins, GitLab CI, Playwright, Cypress and Nodemailer. |
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 Smtp.dev is for
- Fits if you test an app or test suite that sends email and want to read it back
- Works for CI pipelines that need a real inbox to check, with no real mail leaving
Who it is not for
- Skip it if you want to deliver real email: outbound only reaches accounts inside the sandbox
- Tight if you stay on Lite: 1 domain, 50 accounts and messages deleted after 7 days
- Tight if you need catch-all addresses, which start on Pro
- Watch out: messages are deleted at the end of the 7, 30 or 90 day window
- Watch out: the pricing page shows monthly prices only
Good to know
Good for
- Developers testing signup, password-reset and notification emails
- CI pipelines that send mail and assert on what arrived
- Teams that want inboxes on their own test subdomain
Worth knowing
- It is a testing sandbox: on every plan, outbound mail is delivered only to accounts inside the sandbox, not to real inboxes.
- Lite keeps messages for 7 days and allows 1 domain and 50 accounts; catch-all accounts need Pro or Max.
- Messages are deleted automatically at the end of the plan's retention window of 7, 30 or 90 days.
- The pricing page shows monthly prices only and does not mention annual billing.
Part 02 · Pricing
What it costs
Every plan, the free plan, ways to pay less and how prices have moved
$7
A month to start. There is a free plan too
Smtp.dev has a free plan. Paid plans start at $7 per month for Pro.
Lite
$0
1 domain, 50 accounts and 7 days of message retention; plus-sign aliasing but no catch-all.
Pro
$7
per month
5 domains, 25,000 accounts, 30 days of retention, and catch-all and aliasing.
Max
$20
per month
Unlimited domains and accounts, 90 days of retention, and catch-all and aliasing.
The free plan
Lite plan: 1 domain, 50 accounts, messages kept 7 days, with SMTP, IMAP, POP3, API and email audit.
Read from smtp.dev 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
Email testing sandbox with SMTP, IMAP and a REST API. Here is what it does, as its own site describes it, and what it covers: public API, dMARC.
It does the testing job fully, but it never sends real email.
- SMTP, IMAP and POP3 access
- Standard mail clients and libraries connect with ordinary settings, with no SDK to install.
- REST API
- Accounts, messages, domains and tokens can be managed over the API, which is limited to 4096 requests a minute per user.
- Message inspection
- Shows headers, the MIME tree and the raw RFC 5322 source of each message, plus an HTML preview.
- Own-domain receiving
- Pointing a domain's or subdomain's MX record at the sandbox lets it receive mail from any service.
- Deliverability audit
- Checks sender configuration, HTML structure, links and content patterns that spam filters flag, grouped by severity.
- CI use
- Works with any CI system that can send over SMTP, with guides for GitHub Actions, Jenkins and GitLab CI.
Where it runs
- Web
What it works with
- GitHub Actions
- Jenkins
- GitLab CI
- Playwright
- Cypress
- Nodemailer
Smtp.dev is made by SMTP Labs, Inc.
Part 04 · Standing
Where it stands
Its grades against its category, and whether to keep it or make your own
34/50
Other email sending services it is graded above
Smtp.dev's GPA of 2.6 is higher than 34 of the 50 other email sending services we grade, and level with 11.
It stands best on free plan and trial (B, above 35 of 50) and worst on features (C, above 0).
Its paid plans start at $7 a month, against a middle price of $15 for the category: 6 of the 41 others that charge start lower.
On features, ease of use and platforms it scores 2.3 out of 4. 3 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. Smtp.dev’s own letter is outlined.
- BValue for moneyAbove 25 of 50
- BFree plan and trialAbove 35 of 50
- CFeaturesAbove 0 of 50
- CEase of useAbove 7 of 50
- BPlatforms and integrationsAbove 17 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. Smtp.dev 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
Nothing Smtp.dev does is plain enough to make in a weekend. The 2 things listed below take a company.
It is one of the better ones too: its GPA of 2.6 is higher than 34 of the 50 other email sending services we grade. It costs $84 a year.
What you could not
- Reading the reports inbox providers send about your domain.
- It plugs into other products, GitHub Actions, Jenkins and GitLab CI among them, and has an API.
What this rests on. Smtp.dev’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
Mailtrap, MailPace, EmailEngine and Nodemailer
The 4 tools Smtp.dev is most often weighed against, with where each one differs from it.
- 2.6GPA
Mailtrap
Free plan · from $15/mo
Email API and SMTP for sending, with a sandbox for testing emails.
- Smtp.dev also covers dMARC.
- Mailtrap also covers email campaigns and transactional email.
- 2.2GPA
MailPace
Free trial · from $10/mo
EU-hosted transactional email API and SMTP, without open tracking.
- Smtp.dev has a free plan. MailPace does not, though it has a free trial.
- Smtp.dev also covers dMARC.
- MailPace also covers transactional email.
- 1.6GPA
EmailEngine
Free trial · from $199/mo
Self-hosted REST API for Gmail, Microsoft 365 and IMAP mailboxes.
- Smtp.dev has a free plan. EmailEngine does not, though it has a free trial.
- EmailEngine is self-hostable, according to its own site.
- Smtp.dev also covers dMARC.
- 2.6GPA
Nodemailer
Free
Free Node.js library for sending email over SMTP and other transports.
- Nodemailer is open source, according to its own site.
- Smtp.dev also covers dMARC.
- Nodemailer also covers transactional email.
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 Smtp.dev free?
Smtp.dev has a free plan. Lite plan: 1 domain, 50 accounts, messages kept 7 days, with SMTP, IMAP, POP3, API and email audit.
How much does Smtp.dev cost?
Smtp.dev lists 3 plans. Lite: $0.
What platforms does Smtp.dev work on?
Smtp.dev is available on Web.
Does Smtp.dev have an Android app?
No Android app was listed when its pages were read on Nov 13, 2026. Smtp.dev is listed for Web.
Does Smtp.dev have an iPhone app?
No iPhone app was listed when its pages were read on Nov 13, 2026. Smtp.dev is listed for Web.
Is Smtp.dev open source?
Smtp.dev is not described as open source on its own site, as read on Nov 13, 2026.
Does Smtp.dev have an API?
Yes. Smtp.dev offers a public API, according to its own site.
What does Smtp.dev integrate with?
Smtp.dev's listing names GitHub Actions, Jenkins, GitLab CI, Playwright, Cypress and Nodemailer.
Who makes Smtp.dev?
Smtp.dev is made by SMTP Labs, Inc.
What are the alternatives to Smtp.dev?
The closest alternatives to Smtp.dev in our directory are Mailtrap, MailPace, EmailEngine and Nodemailer.
How does Smtp.dev compare with other email sending services?
Smtp.dev's GPA of 2.6 is higher than 34 of the 50 other email sending services we grade, and level with 11.
Is Smtp.dev good value for money?
ToolGPA grades Smtp.dev B for value for money. Its paid plans start at $7 a month, against a middle price of $15 for the category: 6 of the 41 others that charge start lower.
Could I make my own version of Smtp.dev?
Nothing Smtp.dev does is plain enough to make in a weekend. The 2 things listed below take a company.
Where this guide comes from
The prices, plans, platforms and features were read from Smtp.dev’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 Smtp.dev'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 SMTP Labs, Inc. Prices change, so check smtp.dev 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
- Smtp.dev, kept up to dateEverything in this guide, with prices and grades as they are todaytoolgpa.com/tools/smtpdev
- 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, "Smtp.dev: The Insider's Guide", checked Nov 13, 2026. https://toolgpa.com/tools/smtpdev
Know someone choosing between email sending services?
Send them this guide: toolgpa.com/tools/smtpdev/guide
ToolGPA elsewhere: youtube.com/@toolgpa
See our other guides
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- 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 Smtp.dev’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. Smtp.dev is a trademark of its owner, and this guide is not made, paid for or approved by SMTP Labs, Inc. Prices and plans change: check smtp.dev before you buy.