MailTub

Paid AndroidAPIiPhoneLinuxMacSelf-hosted+2

What MailTub is

MailTub is a self-hosted disposable email service for creating temporary inboxes. New messages reach inboxes through WebSocket push instead of repeated polling. A session can hold up to five inboxes, each with an expiry choice of 1 hour, 6 hours, 24 hours or 7 days. Users can export inboxes as an .eml ZIP or structured JSON, and MailTub parses MIME attachments with configurable size caps. It runs as a single Go binary with SQLite and an embedded React interface, or through Docker. The web interface offers dark, light and system themes and can be installed as a progressive web app on mobile or desktop. Alongside SMTP receiving, it offers a REST API, a scriptable CLI and a Prometheus-compatible metrics endpoint. Mailbox creation is limited to 20 per IP per hour. Receiving real email requires a domain with an MX record pointing to the server, port 25 access or redirection, and a matching MAILTUB_DOMAIN setting. MailTub is free, open source and licensed under Apache 2.0.

Who it suits

MailTub suits people who want to host a disposable inbox service themselves and need API or CLI access. Receiving real email requires the listed domain, MX record, port and MAILTUB_DOMAIN setup.

What it does well

Free and Apache 2.0 licensed.
Up to five inboxes per session.
Expiry options range from 1 hour to 7 days.
Exports inboxes as .eml ZIP or JSON.
Offers REST API, CLI and WebSocket updates.

What to know first

Mailbox creation is limited to 20 per IP per hour.
Real email requires domain and server configuration.
API is open by default unless an API key is configured.

Limits

A session can have up to five simultaneous inboxes, with expiry options of 1 hour, 6 hours, 24 hours, or 7 days. Mailbox creation is limited to 20 per IP per hour; defaults cap SMTP messages at 25 MiB, each attachment at 25 MiB, and all attachments in an email at 50 MiB.

Getting started

Open the MailTub project website on GitHub.
Choose a deployment using the single Go binary or Docker.
Configure a domain with an MX record pointing to the server, port 25 access or redirection, and a matching MAILTUB_DOMAIN setting to receive real email.
Open the web interface or use the REST API or scriptable CLI to create and manage inboxes.
Set an expiry of 1 hour, 6 hours, 24 hours, or 7 days for each inbox.

Verdict

MailTub combines temporary inboxes, exports and developer-facing interfaces in a self-hosted service. Check the real-email requirements and creation limit before choosing it.

Questions

How much does MailTub cost?

MailTub is free and open source. The repository identifies its license as Apache 2.0.

Where can MailTub run?

The listed platforms are Android, API, iOS, Linux, macOS, self-hosted, web, and Windows. Deployment options include a single Go binary and Docker.

How many inboxes can a session have?

A session can hold up to five simultaneous inboxes. Each can expire after 1 hour, 6 hours, 24 hours, or 7 days.

What is needed to receive real email?

Receiving real email requires a domain with an MX record pointing to the server, port 25 access or redirection, and a matching MAILTUB_DOMAIN setting.

Does MailTub provide an API or integrations?

It provides a REST API, SMTP receiving, WebSocket updates, a scriptable CLI, and a Prometheus-compatible metrics endpoint. Mailbox caching can optionally use a Redis or Upstash URL.

Does it support attachments and exports?

MailTub parses MIME attachments with configurable per-attachment and total size caps. Users can download inboxes as an .eml ZIP or structured JSON.

Facts from MailTub's own pages

API access: The API is open by default unless an API key is configured; the health endpoint remains public. · github.com, 30 Sept 2026
API and CLI: MailTub provides a REST API and a scriptable CLI for creating, listing, reading, watching, and sending mail. · github.com, 30 Sept 2026
Attachments: MailTub parses MIME attachments and supports configurable per-attachment and total attachment size caps. · github.com, 30 Sept 2026
Deployment: MailTub runs as a single Go binary with SQLite and an embedded React interface, and also provides Docker deployment. · github.com, 30 Sept 2026
Email size limits: Defaults include a 25 MiB SMTP message limit, a 25 MiB per-attachment cap, and a 50 MiB total attachment cap per email. · github.com, 30 Sept 2026
Exports: Users can download an inbox as an .eml ZIP or structured JSON. · github.com, 30 Sept 2026
Inbox limits: A session can have up to five simultaneous inboxes, with mailbox expiry choices of 1 hour, 6 hours, 24 hours, or 7 days. · github.com, 30 Sept 2026
Integrations: It provides a REST API, SMTP receiving, WebSocket updates, and a Prometheus-compatible metrics endpoint. · github.com, 30 Sept 2026
License: The repository identifies the project as Apache 2.0 licensed. · github.com, 30 Sept 2026
Mailbox limits: A session can have up to five simultaneous inboxes, with expiry options of 1 hour, 6 hours, 24 hours, or 7 days. · github.com, 30 Sept 2026
Optional caching: Mailbox caching can optionally use a Redis or Upstash URL. · github.com, 30 Sept 2026
Purpose: MailTub is a self-hosted disposable email service that creates temporary inboxes. · github.com, 30 Sept 2026
Rate limit: Mailbox creation is limited to 20 per IP per hour. · github.com, 30 Sept 2026
Rate limiting: MailTub limits mailbox creation to 20 per IP per hour. · github.com, 30 Sept 2026
Real-time email: New emails appear through WebSocket push, which the project says delivers them in milliseconds without polling. · github.com, 30 Sept 2026
Real-time inboxes: New emails appear through WebSocket push, without polling. · github.com, 30 Sept 2026
Receiving mail requirements: Receiving real email requires a domain with an MX record pointing to the server, port 25 access or redirection, and a matching MAILTUB_DOMAIN setting. · github.com, 30 Sept 2026
Security: The admin panel stores its password as a bcrypt hash and uses HMAC-SHA256 signed session cookies with a 24-hour lifetime. · github.com, 30 Sept 2026
Support: The project asks users to report security vulnerabilities to [email protected]. · github.com, 30 Sept 2026
Support and security contact: The project asks users to report vulnerabilities to [email protected]. · github.com, 30 Sept 2026
User interface: The web interface supports dark, light, or system themes, and can be installed as a progressive web app on mobile and desktop. · github.com, 30 Sept 2026

Where MailTub stands on Freedom251

Disposable Email Services#24 of 25
Temporary email services#43 of 44