Features

The parts you need to send a good email.

Not the parts that come with a manual. Here's everything day3 does, and, just as deliberately, the bloat it leaves out.

Write the email, choose who gets it, send.

One email to one audience. Compose, test, and send it, all on a single screen. No funnels, no approval maze.

Unlimited subscribers. Plain lists you actually understand.

A named list of subscribers. Import them, add them by hand, and filter by status. Pay the same whether it's 200 or 200,000.

One form, installed anywhere you can paste a snippet.

One form, four ways to install it: hosted, embedded, popup, or raw HTML. Double opt-in keeps your list clean from day one.

Land in the inbox, not the spam folder.

Authenticated domains, one-click unsubscribe, and automatic suppression of bad addresses. All standard, not sold separately.

See what happens after you hit send.

One page for deliverability, reputation, and engagement across every campaign: opens, clicks, bounces, complaints, and unsubscribes, with a per-campaign breakdown.

A writing assistant, when you want one.

Draft a campaign from a short brief, get subject lines and preview text, and rewrite what you highlight. Powered by Claude, and included on every paid plan.

All of it, over HTTPS.

One REST API for your app's transactional email, your audiences, and your campaigns, plus an MCP server that turns your AI editor into a composer. Built so migrating from another provider is one script and staying in sync afterwards is a webhook handler.

What day3 deliberately does not do

These are omissions, not a roadmap. If one of them is what you came for, a marketing platform will serve you better and we would rather you knew now.

No automation flows. No onboarding drips, trial nurture, or win-back sequences. Triggers, waits and branches are designed but not shipped, so don't pick day3 on the strength of them.
No A/B testing. No split tests on subject lines or send times. For a changelog going to your whole user base there isn't much to split.
No drag-and-drop template builder. The composer produces clean, inbox-safe formatting from what you type. There is no canvas to arrange blocks on.
No landing pages or CRM. Signup form pages, yes. A website builder, a sales pipeline, or contact scoring, no.
No monetisation layer. No paid subscriptions, ad network, referral programme, or public archive. day3 is not a platform for running a newsletter as a media business.
No agency or multi-account layer. One organisation per account, no client sub-accounts and no white labelling.

Automations, meaning triggers, waits and branches, are designed but not shipped. Everything on the cards above works today.

See it before you commit.

Get started How the pricing works