No account
The free inbox opens in this browser. Sign in only when you need a longer clock or an API key.
Your temporary email
Getting your address
Paste this address into the other tab, then open the inbox to read the mail. No account. About one hour, then it is deleted.
Temporary email
A private inbox for the next hour.
Open a mailby.app address, paste it into a signup, and copy the code when it arrives. Your everyday inbox stays out of it.
What you get before you sign up
About one hour
The free inbox can receive for about an hour. Delete ends it immediately. That address is not reused.
Address is not access
Anyone can send mail to the address. Only this session, or a secret you paste later, can read it.
Built for a signup, a code, or a test
Keep a signup off your real inbox
Use a mailby.app address for a one-time form so the follow-up never lands in the mailbox you actually use.
Copy the code
The message arrives in this session. The code sits beside it, ready to copy.
Read without trackers
The preview blocks remote images, so opening the mail does not load the sender’s pixels.
Reopen with a secret
Save the recovery secret shown once. Paste it on the recover page. It is never put in the URL.
Wait from a test
A Developer plan can create an inbox, wait for the message, and read the code from the API.
Receive only
Mailby accepts mail for the address. It does not relay, and it does not offer SMTP login.
The address is not the password
Anyone who sees the address can send mail to it. They cannot open the inbox. Read access stays with this browser, or with a recovery secret you paste later. That secret is never put in the URL.
A test can wait for the email
Create an inbox, send the mail from your app, and read the code when it arrives. Webhooks are signed. The local SMTP listener on 127.0.0.1:2526 does not relay.
API overviewPOST /api/v1/inboxes
GET /api/v1/inboxes/{id}/otpPremium
Premium is $6 a month, or $35 for the year.
Plan prices are loaded from billing. Open pricing if this list is empty.
Questions people ask first
- What is temporary email?
- A mailby.app address you open for a signup or a code, then delete or let expire. It receives mail. It does not replace the inbox you use every day.
- Who can read the inbox?
- This browser session, or someone who pastes the recovery secret. Knowing the address only lets them send mail to it.
- What happens when it expires?
- The free inbox can receive for about an hour, then the mail is deleted. Delete ends access immediately. That address is not reused.
- Can it be recovered?
- Yes, if you saved the secret shown once. Paste it on the recover page. The secret is never put in the URL.
- Will every website accept it?
- No. Some services block temporary email. Mailby does not bypass those checks.
- When should I use a permanent address?
- When you need the account later, or when the site will send password resets and receipts you must keep.
- Which features require a paid plan?
- Free needs no account. Premium is the only paid plan: every premium domain, unlimited custom domains, multiple addresses, a 30 day clock, and the API. It is $6 a month or $35 for the year.
- How large can a message be?
- The free inbox accepts a message up to 5 MB, attachments included. Premium accepts up to 25 MB. A larger message is refused.
Summary
What is it?
Mailby is temporary email: a disposable inbox you open when a site asks for an address you do not want to keep.
How does it work?
Open Quick Inbox, paste the address, copy the code when it arrives, then delete the inbox or let it expire.
Why use Mailby?
You finish the signup without filling your real mailbox, and knowing the address does not let anyone else read the mail.
Key takeaways
- Free address on mailby.app, no account
- The code is extracted beside the message
- Previews block remote images
- Receive-only, then the inbox is deleted