Quick answer
Mailinator - Mailinator wins for most builders who want a free, no-card testing tier, while Mailtrap wins if you need a real sending product with stricter quota ceilings and a lower entry price for paid usage.
How the free tiers compare
These products overlap on email testing, but they are built around different free-tier shapes. Mailinator’s free plan is centered on disposable public inboxes for QA, with unlimited public inboxes, temporary storage, SMS testing, API access, webhooks, routing rules, and load-testing features, and it does not require a credit card. That makes it strong for teams validating sign-ups, OTPs, and reset flows without setting up much infrastructure. Mailtrap’s free tier is narrower and more productized around both sending and sandbox testing: 4,000 emails per month, 150 per day, 1 domain, 100 contacts, 3 days of logs, 1 user, and a separate sandbox allowance. If you are testing inbox flows and want broad free access, Mailinator is easier to start with. If you need a sending platform that can later scale into deliverability and domain-based emailing, Mailtrap has a clearer paid ladder.
Mailinator vs Mailtrap free tier, side by side
| MailinatorFTV 74 | MailtrapFTV 37 | |
|---|---|---|
| Free plan typeMailinator’s free plan is public and temporary; Mailtrap’s free tier is split across sending and sandbox use. | Public inbox testing | Email API/SMTP plus sandbox testing |
| Inbox / domain modelMailinator’s free tier is broader for disposable inbox creation. | Unlimited public inboxes | 1 domain included |
| Message volumeMailtrap gives explicit sending caps on the free plan. | Not specified on free public plan | 4,000 emails/month and 150 emails/day |
| Storage / logsMailinator’s free plan does not list permanent retention. | Temporary storage | 3 days of email logs retained |
| API accessBoth list API access or description. | Included | Included |
| SMS testing | Included | Not listed |
After you outgrow the free tier
Mailinator’s next step up is a flat paid ladder starting with Verified Pro at $0 with Verification, then Business at $79/month billed yearly, then Business Plus at $159/month billed yearly, and Enterprise at $699 and up custom pricing. Mailtrap’s paid ladder is flatter at the low end, starting at Basic for $15/month, then moving through tiered Business plans at $85, $200, $300, and $450/month, with Enterprise at $750/month. For small-team usage, Mailtrap is cheaper to enter, but Mailinator is cheaper if you specifically need its private-inbox features at the low end only if you qualify for Verified Pro, otherwise its first meaningful paid plan is much higher.
Cost at real usage
| Usage | Mailinator | Mailtrap |
|---|---|---|
| 10k emails/monthMailtrap’s free tier is capped at 4,000 emails/month, so 10k/mo would need the Basic plan. | Free tier does not specify a comparable sending quota | $15/mo |
| 100k emails/monthMailinator Business includes 100K emails/mo. Mailtrap Business is $85/mo at 100K emails/mo. | $79/mo | $85/mo |
| 250k emails/monthMailinator Business Plus tops out at 300K emails/mo. Mailtrap shows a $200/mo Business tier for 250K emails/mo. | $159/mo | $200/mo |
| 500k emails/monthMailinator Enterprise is $699 and up custom pricing with 3MM+ emails/mo. Mailtrap shows $300/mo for 500K emails/mo. | $699 and up custom pricing | $300/mo |
Estimates, not quotes. Usage-based rates change - verify with the vendor's pricing page before committing.
When to pick each one
Pick Mailinator when…
- You need disposable inboxes for sign-up, OTP, password reset, or other message-driven QA.
- You want to start without a credit card and keep using the free tier indefinitely for public inbox testing.
- You need SMS testing, webhooks, routing rules, or load testing as part of verification.
- You care more about testing workflows than about sending production email.
- You expect to use private inboxes later and want a low-cost step up to a paid plan.
Pick Mailtrap when…
- You need an email sending product, not just a testing inbox.
- You want a free tier with real sending quotas, including monthly and daily send limits.
- You need log retention, domains, and contacts as part of your workflow.
- You are planning to move from testing into transactional email and want one vendor path.
- You are okay with a free tier that is more constrained.
Bottom line
For the most common builder use case, Mailinator is the better free-tier pick because it is easier to start, needs no card, and gives you broad testing coverage for inbox-driven workflows. Mailtrap is the better choice if your free-tier decision is really about a future email sending stack, since its free plan is smaller but maps cleanly to a paid delivery product. If you only need to verify emails and OTPs, Mailinator is the cleaner fit. If you need sending and domain-based email operations, Mailtrap is the more direct path.
Read the full listings: Mailinator and Mailtrap. Scores use the FTV methodology at /ftv. Browse more head-to-heads on /compare, or see the top-ranked free tiers on /top.