Turn your VPS into
ESP-grade email infrastructure.

No per-send fees. No per-contact fees.

Mailbird sets up a complete mail server with DKIM, SPF, DMARC, and TLS on any Linux VPS — automatically. Send unlimited email, add unlimited domains, and own every part of your delivery pipeline.

Start free trial See pricing

14-day free trial. No charge until day 15.

~ send your first email

$ curl https://app.mailbird.io/api/v1/emails/send \

-H "Authorization: Bearer mb_live_..." \

-H "Content-Type: application/json" \

-d '{

"from": "hello@yourdomain.com",

"to": "user@example.com",

"subject": "Welcome",

"text": "Hi there!"

201 Created { "id": "eml_abc123", "status": "accepted" }

Your email bill shouldn't grow with your business.

Most ESPs scale your bill with email volume. Mailbird scales with mail servers — $5 per server, per month. Your VPS bills you separately for each server. That's the whole pricing model.

Predictable cost

Send 100,000 emails a month? You'll pay hundreds at most ESPs. Mailbird? Still $5 per server.

Your infrastructure

Your data lives on your VPS. If Mailbird disappears tomorrow, your mail server keeps running. No lock-in. Ever.

ESP-grade by default

DKIM, SPF, DMARC, and TLS configured automatically. Your mail lands in inboxes — not spam folders — without paying extra for it.

From sign-up to first email in minutes.

No mail-server expertise required.

01
Bring a VPS

Any Linux VPS with 1 GB of RAM works. Hetzner, DigitalOcean, Vultr, Hostinger, Linode — about $4-10 a month.
02
Connect it to Mailbird

Provide SSH credentials. Mailbird runs pre-flight checks, then configures DKIM, TLS, and SMTP auth automatically.
03
Add domains and send

Generate DNS records, publish at your registrar, verify. Send via SMTP or REST API. You're live.

Every feature in one plan.

No tiers. No upsells. No artificial limits.

Unlimited emails

Send as many as your VPS handles. No tier limits. No overage fees.

Unlimited domains

Each with its own DKIM key. DNS records generated and verified automatically.

DKIM, SPF, DMARC

Set up automatically during deploy. We generate the DNS records; you publish them once.

Automatic TLS

Trusted certificates issued and renewed automatically. Your mail server speaks TLS from minute one.

Inbound mail

Receive at any address on your domains. View in the dashboard, fetch via API, or react with webhooks.

Webhooks

React to delivered, bounced, and received events. Signed payloads, retries on failure.

REST API

Full programmatic access via REST. SMTP submission also supported.

Observability

Track every email's status from queued to delivered — search, filter, debug.

Your data, your VPS

Mail content, queues, and logs stay on your server. We manage the config, not the contents.

Same price at 1,000 emails as 100,000.

$5 per mail server, per month — or $50/year if you save ~17%. You pay your VPS provider separately — typically $4-10 per server.

$5 /server /month

Unlimited emails (sending and receiving)
Unlimited domains
Add as many mail servers as you need
DKIM, SPF, DMARC, TLS auto-configured
Webhooks and REST API
Email support

Use multiple servers for separate regions, staging, or workload isolation.

Start 14-day free trial

Cancel anytime — no charge until day 15.

Mailbird vs. traditional ESPs

Your bill stays the same. Theirs grows.

	Mailbird	Typical ESP
Pricing model	$5/server/month	Per email or volume tiers
Cost at 100k emails/mo^*	$5	$80–200+
Dedicated IP	Yours, included	Shared, or $30+/month add-on
Domains	Unlimited	Limited per tier
Where data lives	On your VPS	On vendor's infrastructure
Vendor lock-in	None	High

^* Higher volumes require appropriate VPS resources and IP reputation. See FAQ.

Built for developers.

REST API for application code. SMTP submission for everything else (Rails, Django, transactional libraries, legacy apps). Bearer tokens for REST. Username and password for SMTP.

JSON in, JSON out. No XML, no SOAP, no driver libraries to maintain.
Synchronous accept. The send call returns once the SMTP server has accepted the message.
Webhooks for everything else. Delivered, bounced, and received — signed and retried on failure.
Batch endpoint. Up to 200 messages in one request when you need it.

# cURL
curl https://app.mailbird.io/api/v1/emails/send \
  -H "Authorization: Bearer $MAILBIRD_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "from": "hello@yourdomain.com",
    "to": "user@example.com",
    "subject": "Welcome",
    "text": "Hi there!"
  }'

// Node.js
const response = await fetch('https://app.mailbird.io/api/v1/emails/send', {
  method: 'POST',
  headers: {
    'Authorization': `Bearer ${process.env.MAILBIRD_API_KEY}`,
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    from: 'hello@yourdomain.com',
    to: 'user@example.com',
    subject: 'Welcome',
    text: 'Hi there!',
  }),
});

# Python
import os, requests

requests.post(
    'https://app.mailbird.io/api/v1/emails/send',
    headers={'Authorization': f"Bearer {os.environ['MAILBIRD_API_KEY']}"},
    json={
        'from': 'hello@yourdomain.com',
        'to': 'user@example.com',
        'subject': 'Welcome',
        'text': 'Hi there!',
    },
)

# Ruby
require 'net/http'
require 'json'

uri = URI('https://app.mailbird.io/api/v1/emails/send')
req = Net::HTTP::Post.new(uri)
req['Authorization'] = "Bearer #{ENV['MAILBIRD_API_KEY']}"
req['Content-Type'] = 'application/json'
req.body = {
  from: 'hello@yourdomain.com',
  to: 'user@example.com',
  subject: 'Welcome',
  text: 'Hi there!',
}.to_json

Net::HTTP.start(uri.hostname, uri.port, use_ssl: true) { |http| http.request(req) }

Your data. Your infrastructure. Your terms.

The mail server runs on your VPS. Mailbird manages config and observability — the bytes flowing through your mail server never touch us.

If Mailbird shuts down, your server keeps running. Your mail configuration, DKIM keys, and TLS certs all stay on the VPS. You'd lose the dashboard; mail would keep flowing.
You control retention. Delete a sent email — it's gone from the queue and from disk.
GDPR-friendly by design. Email content lives in your jurisdiction of choice — wherever your VPS is.
Open standards, end-to-end. Standard mail protocols, standard DKIM signing, CA-issued TLS — nothing proprietary you can't audit.

Frequently asked questions

Things people ask before signing up.

Getting started

Do I need to know how to set up a mail server?

No. Mailbird handles installation, configuration, and ongoing management. You bring a VPS, provide SSH credentials, and we do the rest.

What kind of VPS do I need?

Any Linux VPS with at least 1 GB of RAM works for moderate volumes (up to ~100K emails/month). Higher volumes benefit from more RAM, more CPU, and possibly multiple IPs. Hetzner, DigitalOcean, Vultr, Linode, Hostinger, and most others all work.

What if my VPS provider blocks port 25?

Some providers block outbound port 25 by default. You can usually request an unblock from their support. Mailbird's pre-flight checks tell you up front if there's a problem.

How long does setup actually take?

From sign-up to first email sent: usually 5–10 minutes. Most of that is publishing DNS records and waiting for them to propagate. The actual install on your VPS takes about 60 seconds. If you're already comfortable with DNS, the whole thing is faster than reading this FAQ.

Pricing

How does pricing work?

Mailbird is $5 per mail server, per month — or $50 per server, per year if you want to save ~17%. Each server is billed independently, so you can mix and match (some monthly, some annual). Most customers run one server; if you need more (for separate regions, staging environments, or workload isolation), each additional server is billed the same way. There's no per-email charge. You pay your VPS provider separately — typically $4–10 per server.

How much email can I actually send?

Volume depends on your VPS's resources and your IP's sending reputation. A small $5/month VPS with a properly warmed sending IP can comfortably handle around 100,000 emails per month. Higher volumes (millions per month) require larger VPSes, mature IP reputation, and often multiple IPs. Mailbird configures the mail stack — actual deliverability at scale also depends on your sending practices, list hygiene, and compliance with anti-spam rules.

Can I use multiple servers?

Yes. Each server is $5/month — billed on the same invoice. Most users add a second server for staging or a different geographic region. There's no cap — add as many as you need.

Capabilities

Can I receive email too?

Yes. Toggle inbound on any domain and publish your MX record. Incoming mail is captured and accessible via the dashboard, the API, or webhooks.

Will my emails actually land in inboxes?

Mailbird configures DKIM, SPF, DMARC, and TLS automatically — proper email authentication from the first send. You send from your VPS's IP, so the reputation that matters is yours, not a shared pool's. For high volumes, warm the IP gradually instead of starting cold. List hygiene, complaint handling, and anti-spam compliance are still your responsibility — those are what no ESP can do for you.

Do you support bulk or marketing email?

Mailbird is optimized for transactional email — receipts, password resets, notifications. You can send marketing email, but you'll want to follow standard list hygiene: explicit opt-in, working unsubscribe headers, and a clean list.

Can I switch from another ESP?

Yes — most users come from Resend, Postmark, SendGrid, or Mailgun. The migration is straightforward: set up Mailbird on a VPS, add your domain, publish DNS records, and update your application to point at Mailbird's API or SMTP credentials. Plan a sending overlap of a few days so the new IP's reputation has time to warm before you cut over fully.

Trust & compliance

What happens if Mailbird goes away?

Your VPS keeps running. Your mail configuration, DKIM keys, and TLS certs stay on your server. You'd lose the management dashboard and the API, but your mail server keeps accepting and delivering messages.

What about compliance — GDPR, CCPA?

Email content lives on your VPS, in your jurisdiction of choice. See our Acceptable Use Policy; if you require a Data Processing Agreement, contact us at support@mailbird.io.

Support

How do I get help?

Email support@mailbird.io. We're a small team and we respond.

Start sending in minutes.

14-day free trial. Cancel anytime — no charge until day 15.

Start free trial

Turn your VPS into ESP-grade email infrastructure.