---
title: "Deliverability"
description: "Bounce, complaint, and spam-placement health, with the thresholds Warmbly acts on."
icon: HeartPulse
---

Deliverability is whether your email actually reaches the inbox, instead of bouncing, getting marked as spam, or being filtered into the junk folder. Warmbly tracks this for every mailbox and every campaign you run, surfaces it on a single dashboard, and acts automatically when a mailbox starts to look risky.

This guide explains what Warmbly measures, the health bands it sorts mailboxes into, the exact thresholds that trigger action, and the built-in protections that keep your sending clean: one-click unsubscribe, pre-send verification, and suppression.

The numbers in this guide are Warmbly's defaults. They are deliberately stricter than the point where mailbox providers like Google or Microsoft start penalizing senders, because the goal is to act before provider-level enforcement hits your reputation.

## The deliverability dashboard

The Deliverability page gives you one live view of how your mailboxes are performing. It updates in real time as new sends, bounces, complaints, and replies come in, so you do not need to refresh.

You can scope the whole dashboard to a time window with the range tabs: `7d`, `30d`, or `90d`.

### Headline rates

At the top of the page are four headline numbers for the selected window:

- **Bounce rate**: the share of sent emails that bounced, shown as a percentage along with the raw counts (for example, bounces out of total sent). This number is highlighted when it reaches `5%` or higher.
- **Complaint rate**: the share of recipients who marked your mail as spam. This number is highlighted when it reaches `0.1%` or higher.
- **Spam placement**: the share of monitored test deliveries that landed in spam or junk, based on seed inbox samples. If there is no seed data yet, this shows a dash.
- **Suppressed**: the number of recipients currently on your active suppression list (see [Suppression](#suppression-stopping-traffic-early) below).

### Trend over time

The "Over time" chart plots a single metric per day across your selected window. You can switch which metric is plotted between **Bounces**, **Complaints**, **Opens**, **Replies**, and **Sent**. Use this to spot a sudden spike: a clean line that jumps on one day usually points to a specific campaign or list problem.

### Window totals

A side panel lists the raw totals for the window: Sent, Opens, Clicks, Replies, Bounces, Complaints, and Unsubscribes. These are the counts behind the rates above.

### Seed inbox placement

When seed (test inbox) data is available, the dashboard shows an **Inbox placement** breakdown: the percentage of seed deliveries that landed in the inbox versus the percentage that landed in spam, along with how many seed samples that is based on.

Seed placement is the most direct signal you have. Bounces and complaints tell you about visible failures, but a message can be delivered "successfully" and still land in the junk folder where no one sees it. Seed inbox placement is how Warmbly catches that.

<Callout type="info" title="Placement needs a sample">
Spam placement and inbox placement only appear once there is enough seed data. A small number of samples can be noisy, so treat a low sample count as a hint, not a verdict. Warmbly only starts acting on placement once it has a meaningful sample (see the bands below).
</Callout>

### Mailboxes and campaigns at risk

Below the charts, two lists rank the mailboxes and campaigns that have bounce or complaint activity in the window, worst first. Each row shows how many emails were sent, the bounce rate, the complaint (spam) rate, and a colored health band chip.

Clicking a campaign row opens that campaign. From the mailboxes list you can jump to **All mailboxes** to manage individual senders.

## Health bands

Warmbly sorts each mailbox into a health band. The band is shown as a colored chip on the dashboard, and it controls how Warmbly treats the mailbox: which bands stay in warmup pools, which get throttled, and which get pulled out entirely.

The four bands you see on the dashboard are:

| Band | Chip color | Meaning |
| --- | --- | --- |
| Healthy | Green | Sending normally. No action needed. |
| Watch | Amber | Early warning signs. Volume lowered, spacing increased, monitoring up. |
| Quarantine | Orange | Removed from the shared warmup pool. Cold sending throttled or paused. |
| Blocked | Red | Blocked from the shared warmup pool. Requires review before re-entry. |

Warmup is a paid feature, and these pool actions apply to the shared paid warmup pool that healthy paying customers depend on. Protecting that shared reputation is the reason the bands exist. For how warmup itself works, see the [Warmup](/guides/warmup) guide.

<Callout type="info" title="Different metrics, different failure modes">
Warmbly does not roll everything into one score. It tracks complaint rate, spam-folder placement, and bounce rate as separate signals, because they fail for different reasons. Any one of them crossing a threshold can move a mailbox into a worse band.
</Callout>

### Sample floors

Warmbly waits for a minimum amount of data before acting on a rate, so a single bad event does not flip a brand-new mailbox into quarantine:

- **Spam placement** needs at least `20` warmup deliveries in the last `7 days` before it counts.
- **Complaints** need at least `100` delivered emails in the last `30 days` before the rate is acted on.

### Exact thresholds

These are the default bands and the metrics that move a mailbox into each one. A mailbox enters a band when it crosses any single threshold listed for that band.

| Band | Spam placement | Complaint rate | Bounce rate | Other triggers |
| --- | --- | --- | --- | --- |
| Watch | `>= 10%` (over `20+` deliveries) | `>= 0.03%` | — | — |
| Quarantine | `>= 20%` | `>= 0.10%` | `>= 5%` | Repeated suspicious warmup-token failures |
| Blocked | `>= 40%` | `>= 0.30%` | `>= 10%` | Clear abuse signals (token forgery patterns, repeated spam flags) |
| Catastrophic | `>= 80%` | — | — | — |

What each band does:

- **Watch**: lower the mailbox's warmup volume, increase spacing between sends, and watch it more closely.
- **Quarantine**: immediately remove the mailbox from the shared paid warmup pool for `7 days`. If the same mailbox is also sending cold campaigns, that sending is throttled or paused. A quarantined mailbox is not selected as a warmup sender or as a warmup recipient.
- **Blocked**: block the mailbox from the shared paid pool for `30 days` and require review before it can re-enter.
- **Catastrophic**: a spam placement of `80%` or higher triggers an immediate long-duration block and a full reputation reset. The mailbox does not return to the shared paid pool automatically.

<Callout type="warn" title="80% spam is not a warning, it is a failure">
If a mailbox is landing in spam most of the time, it is already damaging the shared pool. The bands above are designed to act long before that point. By the time a mailbox would hit a "most mail in spam" level, Warmbly has usually already quarantined or blocked it.
</Callout>

### Re-entry after a block

A blocked mailbox does not automatically come back just because the cooldown elapsed. Before it re-enters the shared paid pool, it has to requalify:

- authentication is still healthy: SPF, DKIM, DMARC (and PTR where relevant)
- no recent provider complaints or hard-bounce spikes
- no recent invalid warmup-token attempts
- spam-folder placement back below `10%` on a fresh probation sample
- re-entry is gradual, starting at low volume (for example `5-10/day` of warmup at first)

## One-click unsubscribe

Warmbly supports one-click unsubscribe (the RFC 8058 standard that Gmail and Yahoo require for bulk senders). When it is enabled, recipients get a native "Unsubscribe" control in their mail client, and a single click opts them out without them having to open your email or click through a landing page.

Why this matters for deliverability:

- making it easy to unsubscribe drives down your complaint rate, because a recipient who can opt out cleanly is far less likely to hit "mark as spam" instead
- Google's bulk-sender guidance requires one-click unsubscribe for marketing and subscribed mail, so it is effectively mandatory for staying in the inbox at volume

When someone unsubscribes, that address is added to your suppression list automatically, so no campaign will mail them again.

## Pre-send verification

Warmbly can verify a recipient address before it sends to them. The point is to catch bad addresses before they turn into bounces, because a high bounce rate is one of the fastest ways to wreck a mailbox's reputation (and one of the `>= 5%` / `>= 10%` thresholds above).

If verification flags an address as undeliverable, Warmbly skips it rather than sending and collecting a hard bounce. This keeps your bounce rate low and your sent volume honest.

<Callout type="info" title="Verification protects your bounce rate">
Bounces are weighed heavily by mailbox providers. Keeping bad addresses out of your sends is cheaper and safer than recovering a mailbox after its bounce rate has already spiked.
</Callout>

## Suppression: stopping traffic early

Suppression is Warmbly's safety net. A suppressed recipient is one that no campaign will email again, no matter which campaign or list they appear on. Warmbly automatically suppresses an address after a clear negative signal:

- a bounce (especially a hard bounce)
- a spam complaint
- an unsubscribe

Campaigns skip suppressed recipients automatically. This is intentional: when a recipient has already bounced or complained, the safest response is to stop sending to them, not to keep trying and collect more negative signals that drag down your rates.

The **Suppressed** count on the dashboard shows how many recipients are currently held back this way.

## How to read your dashboard

A practical way to use the page:

1. Check the four headline rates first. Bounce rate at or above `5%` and complaint rate at or above `0.1%` are the two highlighted danger lines.
2. If a rate looks off, switch the "Over time" chart to that metric and find the day it spiked. That usually points you at one campaign or one imported list.
3. Scroll to **Mailboxes at risk** and **Campaigns at risk**. The band chips tell you which senders Warmbly is already acting on.
4. For any mailbox in Watch, slow it down and let it recover before pushing more volume. For Quarantine or Blocked, leave it out of sending and let it requalify.

The single most important habit: keep complaint rate and spam placement low. A clean reputation with modest volume beats high volume with a rising complaint rate every time.

## Related guides

<Cards>
  <Card title="Warmup" href="/guides/warmup" />
  <Card title="Personalization & expressions" href="/guides/expressions" />
  <Card title="Error codes" href="/api/error-codes" />
</Cards>
