- Email warmup
- Email warmup is the process of gradually sending and engaging with mail from a new or low-volume sending mailbox so that providers like Gmail and Outlook learn to treat it as a trusted human sender. A warmup tool such as Warmerly connects to your mailbox via OAuth and runs continuous, human-like conversations (sends, replies with quoted history, stars, label, mark important, and spam-folder rescue) against an aged peer pool, building the baseline reputation a mailbox needs before any cold outreach is sent.
- Sender reputation
- A score that mailbox providers like Gmail and Microsoft assign to a sender across domain, IP, signing domain, and user-perceived identity. It is shaped by authentication, complaint rate, bounce rate, volume consistency, and user actions on prior messages.
- SPF (Sender Policy Framework)
- A DNS TXT record that authorises which IP addresses may send email on behalf of your domain. Required by Gmail and Yahoo for bulk senders since February 2024.
- DKIM (DomainKeys Identified Mail)
- A cryptographic signature added to outgoing mail that lets receivers verify the message was not tampered with and was authorised by the signing domain. Use a 2048-bit key in 2026.
- DMARC (Domain-based Message Authentication, Reporting and Conformance)
- A DNS policy that tells receivers what to do when SPF or DKIM fail and where to send aggregate reports. Start at p=none with rua reports, then progress to quarantine and reject as confidence grows.
- MTA-STS
- A policy that forces inbound mail to your domain over TLS. Providers read its presence as a signal of operational maturity.
- Inbox placement
- Where a delivered message actually lands: primary inbox, promotions, updates, social, or spam. Distinct from 'delivered' — SMTP can return 250 OK while the message lands in spam.
- Spam recovery (warmup)
- The action of a recipient (or warmup peer) marking a message as not-spam, starring it, replying to it, and moving it back to the inbox. The single strongest positive signal Gmail's neural classifier tracks.
- Peer pool (warmup)
- The set of mailboxes a warmup tool routes your warmup traffic through. A high-quality pool mixes aged, healthy mailboxes with newer ones, and never pairs you only with other brand-new accounts.
- Ramp schedule
- The day-by-day curve of warmup sends from a mailbox. Conservative (4 → 40 per day), Balanced (6 → 60), or Aggressive (10 → 100) are typical defaults, tuned to domain age.
- Health score (Warmerly)
- A 0-100 weighted combination of inbox placement rate, spam recovery rate, reply rate, auth status, bounce rate, and provider response codes. A mailbox is generally ready for cold outreach at 80+ for 5 consecutive days.
Glossary
Every term that matters, in plain English.
The vocabulary of email deliverability is full of acronyms. Here is what each one means, why it matters, and where it shows up in Warmerly.
Ready to put the theory to work?
Warmerly handles every signal in this glossary, automatically, on every mailbox you connect.