Automated email warmup for 98%+ inbox placement
Warmup Inbox builds your sender reputation across Gmail, Outlook, and Yahoo — automatically — so your cold emails reach the inbox, not the spam folder.
Why use email warmup?
New or inactive email accounts often face deliverability challenges, landing emails in spam folders rather than inboxes. Our email warmup tool emulates real user interactions to build a strong sender reputation over time.
Challenges for new senders
Fresh accounts lack the history that providers use to judge trustworthiness, often leading to spam filtering.
Proven improvement
Use cases and statistics show large gains in placement, with users experiencing up to double the open rate after warmup.
Outcomes cold-email teams measure within 30 days
Inbox placement lift
Measured across Gmail, Outlook, and Yahoo after 30-day warmup.
Reply rate on cold sequences
More inboxes reached = more replies. Compounds week over week.
Spam flags on outbound
Fewer reports back to providers; sender reputation stops eroding.
Everything you need to land in the inbox
Network of 30,000+ real inboxes
Your warmup emails are sent to 30,000+ real, active inboxes — not fake or inactive ones. Regularly monitored for quality.
Spam folder avoidance
The tool's design mimics real email activity to bypass spam filters, keeping emails in primary inboxes rather than spam.
Reputation monitoring
Track your reputation score, benchmarked against industry standards, with actionable suggestions to maintain and improve it.
Landing in the primary folder
Designed to place your emails in the Primary folder on platforms like Gmail, avoiding Promotions and increasing open rates.
Instant alerts
Receive alerts if your reputation score falls, giving you the opportunity to pause campaigns and avoid further damage.
Inbox in good standing
Regular interactions and adjustments to your email habits help establish your account as trustworthy, keeping it in top condition.
Why our warmup network actually works
Real inboxes, real conversations, real reputation. Here's what's behind the 30,000+ number.
Real inboxes
Each inbox is a real account with real conversation history. No bots, no auto-generated personas.
Quality monitored
We audit the network weekly. Stale or low-engagement accounts are removed so reputation stays clean.
Diverse provider mix
Gmail, Outlook, Yahoo, Workspace, Microsoft 365, Zoho — reputation builds across every major provider.
A sample of our 30,000+ active accounts
Why a real network beats synthetic warmup
Some tools simulate engagement with bot inboxes and recycled seed lists. Spam filters learn to discount patterns that repeat. Ours never do.
30,000+ real inboxes
- Real people rescue your emails from spam, so providers stop flagging you and your placement climbs
- Reputation builds where your prospects actually are: Gmail, Outlook, and every major provider
- Your gains hold, because genuine conversations give filters nothing to discount
- Results keep improving as the network grows, with zero extra work from you
Bots and seed lists
- Scripted engagement works until filters map the pattern, then your placement drops with it
- Your gains decay the moment the script stops, you rent reputation instead of owning it
- A handful of test domains can't move your standing with the providers your prospects use
- Every customer shares the same bot pool, so you inherit its fingerprint
How to get started
Three steps. Sixty seconds. Zero DNS expertise.
Sign up for Warmup Inbox
Start by creating your account and selecting the email warmup option.
Sign up nowConfigure your inbox
Use our intuitive interface to set your email preferences and begin warmup.
Begin warmup
Activate the tool with one click — we gradually build your sender reputation with our network of real inboxes.
Built for senders who live in the inbox
Lifecycle email that actually lives up to its name.
Nurture sequences, product updates, announcement blasts — warm sending domains means your carefully-written copy actually reaches the people you wrote it for.
Frequently asked questions
What is email warmup?
Email warmup is a process that builds a sender's reputation, helping emails reach inboxes instead of spam folders. Warmup Inbox automates the conversation pattern that providers like Gmail and Outlook use to score sender trust.
How long does warmup take?
You'll see the first improvements within 3 to 7 days, but a full ramp takes 14 to 21 days minimum. Spam filters look for a natural, gradual increase in activity, so rushing the process almost guarantees your domain gets burned. Once you're warmed up, keep warmup running alongside your campaigns to hold your reputation.
Which email providers are supported?
Gmail, Outlook, Yahoo, Google Workspace, Microsoft 365, Zoho, SendGrid, and any custom SMTP provider. Connect via OAuth in under a minute.
What if my deliverability doesn't improve?
Reach out to our team — we'll review your sender setup, DNS records, and sending pattern to identify what's blocking inbox placement. Most issues resolve within the first 30 days of warmup.
Why choose Warmup Inbox?
Trusted by sales and marketing teams for its simplicity, effectiveness, and affordability. Set up in under a minute.