# Land in the inbox, not the spam folder.

Deliverability is whether your email reaches the inbox at all. Bird signs every message, warms your IPs automatically, suppresses bad addresses before they cost you reputation, and watches the major blocklists. The mail you send is the mail that lands.

## Deliverability is a feature, not a hope.

Every account on the Bird Email API gets the primitives below: authenticated sending, managed IP warmup, automatic suppression, and live blocklist monitoring. You don't wire them together yourself. Zillow lifted email open rates 161% after moving deliverability onto Bird, and over Black Friday weekend 2025 Bird processed 19.9 billion emails at a 1.04-second average time to first delivery.

## Five things working for you on every send.

On every send, with no setup step and no add-on SKU.

## You don't write deliverability. You watch it.

Signing, warmup, and suppression are automatic. What you get on top is visibility: pull bounce and complaint rates, mailbox-provider breakdowns, and bounce codes from the stats API, and alert on a trend before it costs you the inbox.

## What healthy sending looks like.

Bird weighs your bounce and complaint rates against volume and history, then acts: healthy traffic sends unthrottled, a degrading reputation gets throttled, and harmful signals pause sending before they torch your domain. As a rule of thumb, hard-bounce rates approaching 5% trigger a pause and healthy lists run well under 1%. Gmail and Yahoo enforce a 0.3% complaint ceiling for bulk senders, and sustained rates above ~0.1% already hurt placement.

## Go deeper in the docs.

Set up authentication with the DKIM, SPF & DMARC guide, plan a ramp with the IP warmup guide, or read the full deliverability guide for the playbook end to end.

## About 40% of the world's commercial email already runs on Bird.

Transactional and marketing email on infrastructure we've run for a decade. Deliverability is one capability of the Bird Email API: sending, dedicated IPs, suppression, and analytics ship with it.