Get your newsletter to the inbox — and keep it there
Mailbox providers and the law both decide whether your email lands in the inbox or the spam folder. These guides break down the rules that matter most for senders in plain English: the Gmail & Yahoo bulk-sender requirements, RFC 8058 one-click unsubscribe, and the CAN-SPAM Act. Read up, then run your own message through the free checker.
Gmail & Yahoo sender requirements
The bulk-sender rules that took effect in February 2024 — SPF, DKIM, DMARC, one-click unsubscribe, and the 0.3% spam-complaint ceiling.
8 min readRFC 8058 one-click unsubscribe
How the List-Unsubscribe and List-Unsubscribe-Post headers work, and how to add a compliant one-click flow that mailbox providers trust.
7 min readThe CAN-SPAM checklist
A plain-English walk through the seven FTC rules every commercial email must follow — from honest headers to a working opt-out.
7 min readFree tools
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