# How warmup works

> What Warmerly's email warmup actually does: the private warmup network, the daily ramp, why warmup never emails your prospects, and how LinkedIn warmup differs.

Source: https://warmerly.com/docs/how-warmup-works

Warmup is the part of Warmerly that builds a mailbox's sending reputation **before** you use it for real outreach. It is a separate system from campaigns, and the single most common misunderstanding about it is worth stating first.

## Warmup never emails your prospects

A mailbox in warmup does not send cold email to anyone on your lists. It exchanges ordinary-looking email with other mailboxes inside Warmerly's private warmup network:

- your mailbox sends warmup messages to network peers,
- peers send warmup messages **back** to your mailbox,
- both sides open and reply to a tuned share of what they receive.

That two-way traffic is what mailbox providers read as "this address is used by a real person who gets real replies." It is invisible to your prospects, and it is the reason warmup works at all, one-directional sending into a void builds nothing.

Your partners are other mailboxes enrolled in warmup: other customers' mailboxes and mailboxes Warmerly runs itself. Warmerly picks them by how busy they are, the mix of providers and each partner's own volume, and tries not to pick the same partner twice within 72 hours. Nothing excludes other mailboxes you own, so two of your own mailboxes can be partners. The [Warmup Network Participation Terms](https://warmerly.com/warmup-terms) say what other participants can see.

Real outbound to real leads happens only through [Campaigns](https://warmerly.com/docs/campaigns). The order that works is: connect the mailbox, authenticate the domain, warm it up, then point campaigns at it.

**Two-way, inside the network.** Your mailbox sends to peers and peers send back. Prospects on your lists are outside it and receive nothing from warmup.

## The ramp

Warmup starts small and increases the mailbox's daily volume over about 30 days rather than sending its full allowance on day one. A brand-new address that suddenly sends dozens of messages looks exactly like a compromised or purchased one, so the ramp is doing reputation work even on the days it looks slow.

The warmup volume starts at about 4 messages a day and climbs steadily: around 8 a day by day 3, 15 by day 7, 25 by day 14, 35 by day 21 and 50 by day 30. Providers also set their own ceiling: 40 a day for Gmail, 30 for Outlook and 25 for Zoho. Poor placement results or a low health score slow the ramp down.

Two numbers bound a mailbox's volume:

| Setting | What it does |
| --- | --- |
| Daily sending limit | The mailbox's own ceiling for campaign sends per day. New mailboxes default to **30/day**. |
| Ramp | While a mailbox is still ramping, the effective daily figure is lower than that ceiling and climbs toward it. |

You can raise a mailbox's daily limit on the mailbox's own settings, but raising it does not skip the ramp, deliverability is earned over days, not set in a field.

**How long should warmup run before I send?** You don't have to wait to launch. A campaign whose mailboxes have had less than 14 days of warmup starts with a **volume ramp** by default: 3 emails per mailbox on day one, climbing as the mailbox warms, so launching the day you connect is safe. Warmerly treats a mailbox's first 14 days as its warming period, and the warmup ramp keeps raising its daily warmup volume until about day 30. A brand-new domain can take longer to earn trust. Keep warmup enabled after campaigns start: it is not a setup step you finish, it is the background activity that keeps the mailbox healthy.

**Illustrative shape, not exact volumes.** Daily volume starts small and climbs toward the mailbox's own daily limit. Raising the limit does not skip the ramp.

## Reputation is cross-provider

Your mailbox can be hosted anywhere: Google Workspace, Microsoft 365, Zoho, IONOS, your own server. The warmup network itself is spread across many providers, so the activity your mailbox takes part in is seen by Gmail, Outlook and the rest regardless of who hosts the sending address. Where your mailbox is hosted does not limit which providers learn to trust it.

## Two different "reply rates"

These look like the same metric and are not. Mixing them up is the second most common warmup question we get.

| Where you see it | What it measures |
| --- | --- |
| The **Positive engagement** check on a mailbox's **Overview** tab (share of warmup emails that got a reply in the last 7 days) | Activity *inside the warmup network only*, how often peer mailboxes replied to warmup mail. Internal, tuned, and says nothing about your prospects. |
| **Reply rate** on a campaign's page | Real leads replying to your real outbound. This is the number that reflects your outreach. |

So a 60% warmup reply rate is not a prediction of campaign performance, and a quiet campaign reply rate is not a warmup fault.

## Checking it is working

Run a [placement test](https://warmerly.com/docs/help/placement-tests) from the **Inbox placement** card on the mailbox's **Health** tab (**Run new test**). It sends probe emails through that mailbox to a small set of target mailboxes and reports where each one landed, inbox, promotions or spam. When a test could only use Warmerly's own warmup mailboxes it is marked as limited accuracy and is a send check, not a verdict. A full test is the most direct check of how a real message from your mailbox is treated, and it is worth more than any single rate on a dashboard.

## LinkedIn warmup is a different mechanism

LinkedIn warmup is not email warmup pointed at another channel. There is no peer network: Warmerly automates real activity on your own connected LinkedIn account, posts, reactions, comments, profile views and connection invitations, generated from the topics, industries and guidelines you configure under **Accounts → your LinkedIn account → LinkedIn warmup settings**.

It requires a paid LinkedIn slot (LinkedIn is sold per account, separately from the base plans, see [Plans and limits](https://warmerly.com/docs/plans-and-limits)).

## Warmup and your plan

Warmup is included on every plan, Free included, and warmup traffic is never metered against a sending allowance. What bounds warmup is how many mailboxes your plan lets you connect.

One exception worth knowing: while a workspace is locked out for billing, **warmup stops along with campaign sending** until the lock clears. Campaigns are not reset, and both resume by themselves within a few minutes of the workspace getting back inside its plan.

## See also

- [Warmup API](https://warmerly.com/docs/warmup): warmup health, stats and trends over HTTP
- [Setting up DKIM](https://warmerly.com/docs/guides/dkim) and [SPF & DMARC](https://warmerly.com/docs/guides/spf-dmarc). Do these before warmup, not after
- [Troubleshooting](https://warmerly.com/docs/troubleshooting): paused mailboxes, placement problems, DKIM false alarms

## More in Using Warmerly

- [FAQ](https://warmerly.com/docs/faq): Short answers to the questions Warmerly users ask most: what warmup does, how long it takes, what plans…
- [How our email infrastructure works](https://warmerly.com/docs/infrastructure): How mail reaches and leaves a Warmerly hosted mailbox: the MX, SPF, DKIM and DMARC records you publish,…
- [Plans & limits](https://warmerly.com/docs/plans-and-limits): What each Warmerly plan includes, how mailbox and campaign limits are enforced, and which allowances reset…