A free MailSlurp alternative for reading verification emails in tests

receivemail.dev is a free, no-signup disposable inbox you read over HTTP. Here's how it compares to MailSlurp, and when each one is the right choice.

MailSlurp is a full email-infrastructure API — it can send and receive, gives you SMTP/IMAP access, permanent inboxes, custom domains, attachments, phone numbers, team accounts and a SOC 2 option. If you need that, MailSlurp is a solid choice and this page won't talk you out of it.

But a lot of people reach for MailSlurp for one narrow job: in an automated test, sign up for something and read the verification email back. For that job specifically, you don't need an email platform — you need a throwaway address you can poll. That's all receivemail.dev does, and it does it free with no signup.

Side by side

	receivemail.dev	MailSlurp
Price	Free	Free tier, then paid plans (from ~$20/mo as of 2026 — see their pricing page)
Signup / account	None	Required
API key to create an inbox	No	Yes
Receive email via API	Yes	Yes
Send email	No	Yes
SMTP / IMAP access	No	Yes
Permanent inboxes	No — up to 60 min TTL	Yes
Custom domains	No	Yes (paid)
Phone / SMS	No (see sms-florin)	Yes
Rate limit	20 inbox creations / min per IP	Plan-dependent
Hosting	Cloudflare Workers	Managed SaaS

MailSlurp's exact free-tier limits and plan prices change over time — check mailslurp.com/pricing for the current numbers.

When receivemail.dev is the better fit

• Your test just needs to read a verification link or code — nothing more.
• You don't want to manage another API key, plan, or billing relationship.
• It's a hobby project, an open-source repo's CI, or a proof of concept.
• You want contributors to run the test suite without signing up for anything.
• You only ever receive; you never need to send from the address.

When to stay on MailSlurp (or move to it)

• You need to send email, not just receive.
• You need inboxes that persist for days or weeks.
• You need SMTP/IMAP, custom domains, attachments handling, or webhooks.
• You need team accounts, audit logs, or SOC 2 for compliance.
• You're running high volume and want a paid SLA behind it.

Migrating a test

If your test currently does "create MailSlurp inbox → sign up → wait for email", the receivemail.dev version is:

# create a mailbox — no key, no account
resp=$(curl -s -X POST https://receivemail.dev/mailboxes)
addr=$(echo "$resp" | jq -r .address)
secret=$(echo "$resp" | jq -r .secret)

# ... run your signup against $addr ...

# poll for the verification email
curl -s "https://receivemail.dev/mailboxes/$addr/messages" \
  -H "Authorization: Bearer $secret"
# => {"address":"...","messages":[{"from_address":"...","subject":"...","body_text":"..."}]}

There's a fuller walkthrough (shell + Playwright) in the CI testing guide.

Other alternatives people compare

• Mailinator — public inboxes are free but shared/visible to anyone; private inboxes and API access are paid.
• Mailosaur — email and SMS testing, server-based, paid with a trial. Good if you want both channels in one paid tool.
• Self-hosted (Mailpit, MailHog) — great when the email is sent by your own app on the same network; not usable when a third party sends to a public address.