UniOne

Sandbox domain

A sandbox domain is a temporary domain that you can obtain immediately following your signup with UniOne. The domain is already verified, and you can use it as a sending domain to test your email integration while you are setting up your own domain.

Important: you will be able to only send emails to confirmed addresses you add manually.

Benefits of using

  • Instant onboarding: start sending test emails right after signup, without verifying your primary domain.
  • Ideal for developers: test your integrations, templates and automation logic.
  • Security and control: sending is allowed to confirmed addresses only.

How to obtain a sandbox domain

  1. Open the Sending domains page in your account.
  2. Click Get a test domain.
  3. A new domain is created automatically and will be instantly available for sending – now, you can use any email address ending with @sandbox-xxxxxxx.unionemailer.com (use the name of the sandbox domain that has been assigned to you) as a “From” email address when sending the messages.
  4. The new domain is shown in your domains list with a sandbox tag.

The sandbox domain is valid for 31 days. After that, it will be automatically deleted, but you can create a new one if needed.

How to add the recipients’ addresses to test sending

  1. Press Settings in your domains list or open the Account – General – Confirmed emails page.
  2. Your account email address is added and available for tests as a “To” email address by default (even though not displayed on the “Confirmed emails” page).
  3. To add another address:
    • Press Add
    • Enter an email address
    • Verify the address by following a link in the verification email
    • After the verification, the address will be available for sending test emails as “To” email address.

A maximum of 10 addresses is allowed, including your primary account email.

Frequently asked questions

Can I use a sandbox domain for a regular campaign?

No. Sandbox domains are created exclusively for testing purposes and cannot be used for marketing or transactional mailings.

Do you charge for the emails sent from sandbox domains?

Yes, these emails are charged according to your current plan (also available in a “Free” plan), and are limited to 100 emails per day.

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