Compare email testing tools
A free Mailosaur alternative for email tests
Mailosaur is a full email and SMS testing platform with SDKs for many languages. If your tests only need to receive an email and read the code or link in it, Free Domain Mail does that on a domain you own, and the first domain is free.
Mailosaur details checked on 8 October 2026 · First domain free · Receive-only
Switching takes four steps
- Add a domain or subdomain you own. Use a spare domain or a subdomain such as qa.yourcompany.com, because its MX record will point here.
- Add two DNS records. A TXT record proves ownership and an MX record sends mail to mx.freedomainmail.com.
- Create an API key. Keys are created in your account and sent as a Bearer token.
- Wait for the code in your test. Call /api/v1/code with wait=60; the request returns as soon as the email arrives.
Free Domain Mail vs Mailosaur
| Free Domain Mail | Mailosaur | |
|---|---|---|
| Free plan | One custom domain, free | No free plan; 14-day trial |
| Cheapest paid plan | First domain free; extra domains are billed per domain | Personal: $24 a month, or $20 a month billed yearly |
| Monthly email limit | No monthly quota | 15,000 inbound emails a month on Personal |
| Receive at a domain you own | Yes, on the free plan | Enterprise plan only; other plans use a mailosaur.net subdomain |
| Catch-all (any address) | Yes, every address at your domain | Yes, every address at the inbox's subdomain |
| API | REST with JSON; any HTTP client | REST plus official SDKs for Node, Java, Ruby, Python, .NET, PHP and Go |
| SMS testing | No | Yes, from $37.50 a month |
| Reply or forward | No, receive-only | Yes, on the Core plan |
When Mailosaur is the better choice
Pick Mailosaur if you want official SDKs, SMS testing, several team seats, or the ability to reply to and forward test messages. Free Domain Mail also does not store attachment files, only their name, size and type, so tests that must open an attachment need another tool.
Pick Free Domain Mail if your tests sign up, wait for an email and read a code or a link, and you want that on your own domain without a monthly subscription.
Works with Playwright, Cypress and any test runner
There is no SDK to install: the API is plain HTTPS and JSON, so a fetch call from Playwright, Cypress, Selenium or a CI script is enough. The code endpoint extracts the one-time code for you, and the links endpoint returns verification links.
How we compared
Mailosaur details come from its own pricing page and documentation (mailosaur.com/pricing and mailosaur.com/docs), read on 8 October 2026. Plans and prices change, so check their site before you decide. Free Domain Mail is not affiliated with Mailosaur; Mailosaur is a trademark of its owner.
Common questions
Is there an SDK?
No official SDK. The API is a small REST interface, so any HTTP client works; the API docs include curl, Node and Python examples.
What are the API limits?
60 requests a minute per API key. A request with wait holds for up to 60 seconds until a matching email arrives.
Can I test attachments?
Only their name, size and type. Attachment files are never stored.
Is it free?
The first custom domain is free, with no monthly email quota. Additional domains are billed per domain.