The open-source
email platform
Transactional email, marketing campaigns, and automated workflows, all against one contact list.
Transactional
Password reset
Campaign
Sent to 12,480 contacts
Ana Ruiz
ana@acme.com
Workflow
Onboarding, step 2 of 4
Segment
Pro customers
Built into products at
Simple to start. Serious at scale.
Domain
acme.com
- SPFVerified
- DKIMVerified
Ready to send
Sending in five minutes
Add your domain, add three DNS records, send. No onboarding call, no warm-up project.
October usage
- 48,210 contacts
- Free
- 10,000 emails sent
- $10.00
Pay per email, never per contact
Store as many contacts as you like for free. Your bill follows what you send, not how big your list is.
No lock-in
Plunk is open source under AGPL-3.0. Use our EU cloud, or run the same code on your own servers.
Everything you need. Nothing you don’t.
Every plan includes all of it.
Trigger
Contact signs up
Send email
Welcome to Acme
Thanks for signing up. Here is how to get started.
Condition
Opened the welcome email?
Workflows
Automation you can see end to end
Start a sequence from anything a contact does in your product. The emails, the waiting and the branching run from there.
How workflows workSegment
Pro, gone quiet
- Plan is Pro
- Last seen over 30 days ago
2,455
contacts
Updated just now
Tom Bakker
Joined the segment
Priya Nair
Left after upgrading
Segments
Audiences that stay current
A segment is a query, re-run every time you use it. The same campaign sent tomorrow reaches tomorrow’s audience.
How segments workAlso in every plan
- Bounce rate
- 0.4%
- Complaint rate
- 0.01%
Reputation monitoring
Bounce and complaint rates tracked for you, with a warning before they become a problem.
One contact, complete history.
At most vendors a receipt, a newsletter and a reply live in three products, on three lists. Here they are one feed you can segment and trigger from.
Ana Ruiz
ana@acme.com
- TransactionalReceipt #3980 delivered2d
- CampaignOpened “August update”5d
- InboundReplied “Thanks, all sorted”1w
- WorkflowFinished “Onboarding”3w
Your agent can run your email.
Connect Claude, Cursor, or any Model Context Protocol client to your project.
Win back the Pro customers who have gone quiet.
Drafted “We miss you” for 2,431 contacts.
Send this campaign to 2,431 people?
Your agent works across contacts, segments, campaigns and workflows, the same ground the dashboard covers.
Anything that sends email waits for your approval first.
Explore the MCP serverReplace your email stack
Most teams pay for two of these at once.
Simple. Transparent.
Pay per email sent. Contacts are free, however many you store.
Or stay on the free plan: 1,000 emails a month, unlimited contacts.
For the same plan, others charge
What customers say
“Transparent and intuitive UI, extremely easy setup & automation and great support.”
Artur CzemielFounder at GraphQL Editor“Lots of care put into Plunk”
Jonni LundyFounding Operations Manager at Resend“I've been using Plunk for building & sending out marketing emails and genuinely love it!”
Joe AshwellFounder at UnwindHR“I loved the ease of use, beautiful UI and great UX. Everything simply works.”
Alisson LealFounder at Brapi“Simple to use, efficient and no regrets!”
Noah Di GesuFounder at Smoothey“Clean design, easy to understand, fair pricing.”
Pierre JacquelFounder at LandinglyFrequently asked questions
Start sending in 5 minutes.
Start on the free plan with 1,000 emails a month, no credit card needed. When you need more, every email is $0.001, with unlimited contacts and every feature included.