Mailscale is a cold email infrastructure tool claiming 95-100% deliverability for professional inboxes with account setup in under 60 seconds.

Mailscale gradually sends low-volume, natural-looking emails from new accounts to build sender reputation over time. The platform owns full infrastructure including SMTP servers and IP pools. With 95-100% deliverability claims for Gmail and Outlook, users can expect 40-70% open rates, which is 2-3 times higher than the average international email open rate of 21%. However, there is a setup waiting period of a few weeks before campaigns can begin.
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Founded
G2 Rating
Starting Price
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Starting Price
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Founded
MXToolbox is a purpose-built online diagnostic platform that helps teams perform MX record lookups, DNS checks, blacklist monitoring, SMTP diagnostics, and track email deliverability in real time.