A Warmy alternative for a steadier start.
Warm up your sender, see where messages land and check your campaign before launch. Keep your sending provider and follow a gradual schedule with MailSlurp.
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Reach customers across every major inbox.
Build sending history gradually and check placement across available Gmail, Outlook, Yahoo, and other provider samples as your schedule progresses.
Track inbox, Promotions, spam, and not-received results throughout the ramp to make informed decisions before increasing campaign volume.
Improve inbox placement
Reach personal inboxes
Improve reach across the personal inboxes customers use every day, with placement results for each provider.
Reach business inboxes
Check available Microsoft 365 and Google Workspace samples before increasing business email volume.
Move further from spam
Compare inbox and spam results over time to see whether your sender is ready for more volume.
Build the reputation behind every campaign.
New and recovering senders need a record of consistent, successful delivery. MailSlurp creates that history before launches, promotions, lifecycle messages, and customer notifications depend on it.
Volume grows in measured steps while receipt, placement, and sender-health observations stay visible.
Build sender reputation
Grow without sudden spikes
Increase sending volume in steady steps that build trust instead of triggering the reputation damage caused by abrupt spikes.
Keep the sender healthy
Keep authentication, domain health, and blocklist signals in view while the sender builds a stronger delivery record.
Recover lost trust
Use a measured recovery schedule to observe an existing sender and decide when to increase volume.
Protect deliverability while volume grows.
MailSlurp uses controlled inbox receipts, delivery failures, domain health, Gmail Postmaster data, and placement tests to choose the next target. Strong signals keep the ramp moving; weaker signals slow it before customer reach drops.
Use each step to assess delivery before increasing volume. Placement also depends on your authentication, content, and recipient engagement.
Start adaptive warmup
Know exactly where mail lands
Measure inbox, Promotions, spam, and not-received outcomes instead of treating provider acceptance as the finish line.
Catch placement changes early
See when inbox reach changes during the ramp and adjust before important customer campaigns are affected.
Keep the team ahead
Bring placement changes into Slack or Microsoft Teams so the people protecting deliverability can act quickly.
Warm up every sender you already use.
Connect your provider through a supported native integration or authenticated SMTP, then warm up the mailbox, domain, and identity used for your customer email.
Use SendGrid, Resend, Amazon SES, Mailgun, Postmark, Gmail, Microsoft 365, Yahoo, Zoho, Fastmail, Brevo, Mailjet, and more.
Connect your provider
How to switch from Warmy
Keep the sender your campaigns already use. Connect it, choose a measured pace and review the next result.
Connect the sender you already use
Keep your mailbox or sending service. Connect SendGrid, Resend, Mailgun or Postmark directly, or use authenticated SMTP with a supported provider. Verify the From address and complete a test delivery before starting. Find the steps for your service in the provider setup guides.
Increase volume gradually
Choose a new-sender or recovery schedule, set a daily target and select your sending hours. MailSlurp's adaptive pacing uses available delivery and sender signals to adjust the next target. You can pause the program while you investigate a problem.
For example, if sends repeatedly fail, check the provider connection before adding more traffic. Include your normal campaigns when planning the sender's total volume.
See where messages land
A successful send confirms that your provider accepted the message. A completed placement check tells you whether the tested mailbox put it in the inbox or spam. Compare equivalent provider samples over time, and investigate a worsening result before increasing volume. The warmup results guide explains what each check can tell you.
Before launch, send your actual campaign through its normal email provider. Use MailSlurp to test its placement, preview it on phones and desktops, and catch broken links and images. A warmup schedule alone cannot tell you whether that campaign is ready.
Questions before you switch?
Why choose MailSlurp as a Warmy alternative?
MailSlurp brings sender warmup and campaign testing together. Warmy documents warmup and placement checks; with MailSlurp, your team can also preview the delivered campaign on real email clients and devices, check its links and images, and test where it lands. Work in the app or use the API to automate recurring checks. Explore MailSlurp email warmup. Read Warmy's placement documentation.
Can I use this for HubSpot marketing emails?
Test a HubSpot marketing campaign through HubSpot's actual campaign sending path. It can use different infrastructure from a connected sales mailbox, so warming that mailbox does not establish the campaign's placement. The HubSpot guide explains how to plan the checks for each path. Read the HubSpot warmup guide.
Which plans include email warmup?
Email warmup is available with Pro and Growth. Compare sender capacity, included credits and provider placement coverage for your workload. Sending usage is billed beyond included credits; current allowances and usage prices are shown with the plans. Compare current warmup plans.
Get your sender ready for the next campaign.
Choose the sender capacity and placement coverage your team needs.
