The Plunk Insider’s Guide
Everything we know about Plunk 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.
Plunk
The Insider’s Guide
Open-source email platform for transactional and marketing mail
Every plan, grade, refund rule and rival among email sending services, read from Plunk’s own pages.
Made by Plunk · 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 Plunk’s own pages, its app-store listings and our grades. Every fact in it is on Plunk’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
Plunk is an open-source email platform that covers transactional email, campaigns and event-triggered workflows against one contact list. The hosted version runs in the EU and bills per email sent rather than per contact, and the same code can be self-hosted under the AGPL-3.0 license.
To get you started, here are 9 things to know about Plunk, taken from its own pages and our grades.
- 1
Best for open-source email sending at $0.001 an email
Plunk covers transactional email, campaigns and workflows against one contact list, and bills $0.001 per email with no monthly fee.
- 2
What it costs
Paid plans start at $0.001 per email sent.
- 3
There is a free plan
1,000 emails per month with unlimited contacts and every feature, with Plunk branding on emails.
- 4
It runs on Web
Web.
- 5
Transactional email
Send single emails through a REST API or an SMTP relay, from your own domain with DKIM signing.
- 6
Campaigns and newsletters
Broadcasts go to the whole contact list or to a segment, with a visual and an HTML editor and open and click tracking.
- 7
Workflows
Event-triggered sequences with delays, conditions and webhook steps, started by something a contact does in your product.
- 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
To replace Plunk 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.
Plunk at a glance
- Pricing
- Free plan, from $0.001 per email sent
- Free plan
- Yes
- Free trial
- None stated
- Runs on
- Web
- Made by
- Plunk
- Category
- Email Sending Services
- Our grade
- 2.6 GPA, good
The report card
Best for open-source email sending at $0.001 an email
Plunk covers transactional email, campaigns and workflows against one contact list, and bills $0.001 per email with no monthly fee. The free plan stops at 1,000 emails a month with Plunk branding on every message.
| Subject | Grade | Comment |
|---|---|---|
| Value for money | B | No monthly fee; $0.001 per email, so 10,000 emails cost $10, near the cheapest quarter of $9 for sending tools. Cost grows with volume. |
| Free plan and trial | C | Free for 1,000 emails a month with unlimited contacts and every feature, but emails carry Plunk branding. |
| Features | B | Transactional email, campaigns, workflows, segments and inbound email. The listing shows no gap in the core job. |
| Ease of use | C | No store rating on record. It is built for developers and can be self-hosted under AGPL-3.0. |
| Platforms and integrations | B | Web, with Amazon SES and Docker listed. No apps, and the hosted service is in the EU. |
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 Plunk is for
- Fits if you send a few thousand emails a month and want pay-as-you-go
- Works for developers who might self-host it later
Who it is not for
- Tight if you send more than 1,000 emails a month on the free plan, which also adds Plunk branding
- Pricey if your volume grows, since it is a flat $0.001 on every email
- Watch out: self-hosting under AGPL-3.0 carries that licence's obligations
- Watch out: the hosted service runs in the EU
Good to know
Good for
- Developers who want transactional and marketing email in one tool
- Teams with big contact lists, since the bill follows sends and not contacts
- Teams that want the option to self-host the same code
Worth knowing
- The free plan stops at 1,000 emails a month and puts Plunk branding on emails.
- The paid plan has no monthly fee: it is $0.001 per email, so cost scales directly with volume.
- The hosted service is in the EU; self-hosting under AGPL-3.0 carries that license's obligations.
Part 02 · Pricing
What it costs
Every plan, the free plan, ways to pay less and how prices have moved
$0.001
To start. There is a free plan too
Plunk has a free plan. Paid plans start at $0.001 per email sent.
Free forever
$0
1,000 emails a month and unlimited contacts. Every feature is included, but emails carry Plunk branding.
Pay as you grow
$0.001
per email sent, no monthly fee
Removes the Plunk branding and the 1,000-email cap, with a monthly spend cap you can set. The vendor's example shows 10,000 emails costing $10.
The free plan
1,000 emails per month with unlimited contacts and every feature, with Plunk branding on emails.
Read from useplunk.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 platform for transactional and marketing mail. Here is what it does, as its own site describes it, and what it covers: open source, self-hostable, public API, workflow automation, email campaigns, transactional email.
Transactional email, campaigns, workflows, segments and inbound email.
- Transactional email
- Send single emails through a REST API or an SMTP relay, from your own domain with DKIM signing.
- Campaigns and newsletters
- Broadcasts go to the whole contact list or to a segment, with a visual and an HTML editor and open and click tracking.
- Workflows
- Event-triggered sequences with delays, conditions and webhook steps, started by something a contact does in your product.
- Segments
- Dynamic segments are queries that re-run each time they are used, so a campaign reaches the current audience.
- Inbound email
- Addresses at your domain can receive mail, and replies become contacts that can start workflows.
- Self-hosting
- The code is open source under AGPL-3.0 and can be deployed with Docker Compose on your own servers.
Where it runs
- Web
What it works with
- Amazon SES
- Docker
Plunk is made by Plunk.
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
Plunk'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 features (B, above 30 of 50) and worst on ease of use (C, above 7).
Each grade against the category
Every bar is all 51 email sending services we grade, cut by the letter each got. Plunk’s own letter is outlined.
- BValue for moneyAbove 25 of 50
- CFree plan and trialAbove 11 of 50
- BFeaturesAbove 30 of 50
- CEase of useAbove 7 of 50
- BPlatforms and integrationsAbove 17 of 50
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 Plunk 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.
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. Plunk 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.
- Newsletters sent to thousands of people that still reach the inbox.
- Connections to other products, each kept working as those products change.
- The depth: we grade its features B, which means it covers the whole job.
What this rests on. Plunk’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
Resend, Twilio SendGrid, Mailgun, Postmark and Amazon SES
The 5 tools Plunk is most often weighed against, with where each one differs from it.
- 2.6GPA
Resend
Free plan · from $20/mo
Developer email API with React Email templates and a free tier.
- Plunk is open source and self-hostable, according to its own site.
- Plunk also covers workflow automation.
- 2.6GPA
Twilio SendGrid
Free trial · from $19.95/mo
Twilio's email API and SMTP service, priced by monthly email volume.
- Plunk has a free plan. Twilio SendGrid does not, though it has a free trial.
- Plunk is open source and self-hostable, according to its own site.
- Plunk also covers workflow automation and email campaigns.
- 2.4GPA
Mailgun
Free plan · from $15/mo
Email API and SMTP relay for developers, with list validation.
- Plunk is open source and self-hostable, according to its own site.
- Plunk also covers workflow automation and email campaigns.
- Mailgun also covers email verification.
- 2.2GPA
Postmark
Free plan · from $15/mo
Transactional email API and SMTP, with broadcasts on a separate stream.
- Plunk is open source and self-hostable, according to its own site.
- Plunk also covers workflow automation and email campaigns.
- Postmark also covers dMARC.
- 2.8GPA
Amazon SES
Free trial
AWS email sending and receiving, paid per 1,000 emails.
- Plunk has a free plan. Amazon SES does not, though it has a free trial.
- Plunk is open source and self-hostable, according to its own site.
- Plunk also covers workflow automation and email campaigns.
Part 06 · Questions
Quick answers
The questions people ask about it, each answered in a line or two
12
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 Plunk free?
Plunk has a free plan. 1,000 emails per month with unlimited contacts and every feature, with Plunk branding on emails.
How much does Plunk cost?
Plunk lists 2 plans. Free forever: $0.
What platforms does Plunk work on?
Plunk is available on Web.
Does Plunk have an Android app?
No Android app was listed when its pages were read on Nov 13, 2026. Plunk is listed for Web.
Does Plunk have an iPhone app?
No iPhone app was listed when its pages were read on Nov 13, 2026. Plunk is listed for Web.
Is Plunk open source?
Yes. Plunk is open source, according to its own site.
Does Plunk have an API?
Yes. Plunk offers a public API, according to its own site.
What does Plunk integrate with?
Plunk's listing names Amazon SES and Docker. A listing names up to eight integrations, so it may connect to more.
Who makes Plunk?
Plunk is made by a company of the same name.
What are the alternatives to Plunk?
The closest alternatives to Plunk in our directory are Resend, Twilio SendGrid, Mailgun, Postmark and Amazon SES.
How does Plunk compare with other email sending services?
Plunk's GPA of 2.6 is higher than 34 of the 50 other email sending services we grade, and level with 11.
Could I make my own version of Plunk?
To replace Plunk 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 Plunk’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 Plunk'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 Plunk. Prices change, so check useplunk.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
- Plunk, kept up to dateEverything in this guide, with prices and grades as they are todaytoolgpa.com/tools/plunk
- 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, "Plunk: The Insider's Guide", checked Nov 13, 2026. https://toolgpa.com/tools/plunk
Know someone choosing between email sending services?
Send them this guide: toolgpa.com/tools/plunk/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 Plunk’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. Plunk is a trademark of its owner, and this guide is not made, paid for or approved by Plunk. Prices and plans change: check useplunk.com before you buy.