Warmup that adapts to keep your mailbox healthy.
SendKit warmup gradually builds your sender reputation by exchanging real emails with real accounts. Opens, replies, and spam rescues happen automatically. When health dips, warmup auto-adjusts volume and timing to protect your mailbox.
Lambda Group
Build reputation before you send a single campaign.
Opens, replies, and spam rescues from real accounts — the signals ESPs actually use to evaluate senders.
When metrics drop, SendKit automatically adjusts volume and settings to heal the mailbox instead of making it worse.
Set starting volume, daily increase, and target. Adjust anytime, or let auto-throttle handle it.
Inbox rate, spam rate, bounce rate, and reply rate per mailbox so you know exactly when it's ready.
Real engagement, not just volume.
Choose your starting volume, daily increase, and target. SendKit checks your DNS (SPF, DKIM, DMARC) before warmup begins so nothing holds you back.
Warmup emails are sent to real accounts in the network. They get opened, replied to, and pulled out of spam — the signals ESPs use to decide if you're trustworthy.
If bounce rates rise or spam placement increases, SendKit automatically throttles volume and adjusts settings to heal the mailbox. You don't have to watch it.
Bought 10 sending domains? Turn on warmup for all of them. They'll build reputation in parallel while you set up campaigns.
A mailbox landed in spam? Warmup gradually rebuilds trust with controlled volume and real engagement signals.
Between campaigns, warmup keeps your mailboxes active so reputation doesn't decay from inactivity.
Why most warmup tools get flagged.
Warmup that adjusts itself, not just runs on autopilot
Most warmup tools blast a fixed volume and hope for the best. SendKit monitors health in real time and auto-throttles when things look off — adjusting volume and timing to protect the mailbox instead of letting it burn.
Set-and-forget warmup that actually protects you
Other tools ramp volume on a fixed schedule regardless of what's happening. If your mailbox starts landing in spam, they keep sending at the same rate. SendKit detects the problem and auto-throttles — reducing volume, adjusting timing, and healing the mailbox before real damage is done.
Real engagement, not just volume
Volume alone doesn't build reputation. ESPs care about engagement — opens, replies, and spam rescues. SendKit warmup generates real engagement from real accounts, building the signals that actually move you from spam to inbox.
Got questions? We've got answers.
SendKit sends emails from your mailbox to real accounts in a warmup network. Those accounts open, reply to, and rescue your emails from spam — building the engagement signals ESPs use to evaluate your sender reputation. If health dips, volume and settings auto-adjust to protect the mailbox.
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