Domain warm-up is the practice of sending gradually increasing volumes from a new domain or mailbox, starting at a handful of messages a day to engaged recipients and ramping over two to four weeks, so that mailbox providers observe good behaviour before real campaigns begin. Warm-up tools automate it by exchanging and replying to messages within a network. The investment is wasted if the first real campaign goes to an unverified list: three weeks of warm-up can be undone in one send that bounces at 10%.
Warm-up is measured by the daily volume reached without deliverability loss and by Postmaster reputation band at the end. A common schedule is 10 to 20 messages a day in week one, doubling weekly to a ceiling of 100 to 200 per mailbox per day for cold outreach.
The rule for the first real campaign is stricter than for later ones: confirmed-valid addresses only, no catch-all, no unknown, and a volume well under the ceiling. The cold email checklist lists the pre-send checks.
Three new domains are warmed for 21 days to 120 messages a day each. The first campaign of 1,800 contacts is verified: 1,340 confirmed valid are sent at 60 a day per domain, the 460 flagged are held. Bounce rate 0.3%, reputation stays high, and volume ramps to the ceiling over the next fortnight.
Verify a list or a single address. 100 free checks a month, unknowns refunded.
Verify Leads - FreeAyoub built BounceZero's 5-stage validation pipeline, its dedicated BGP-announced IP infrastructure, and the Patroni HA PostgreSQL cluster behind every verification. Previously built high-volume email delivery infrastructure. Trained at 1337 Benguerir (École 42 network, 2019). Open-source: bgp_analyzer.