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Replies, analytics, AI

Deliverability

Capability Reviewed · not yet fact-checked

In short

How does Reply protect email deliverability and sender reputation?

Reply protects sending in layers: MailToaster warm-up with configurable profiles, ramp-up mode on by default for new email accounts (10 per day rising by 3 to 100), a weekly domain Health Checker for SPF, DKIM, DMARC, MX, and rDNS, Google Postmaster spam-rate monitoring, custom tracking domains, AI template scoring, and bounce thresholds that stop a step.

At a glance

What it doesWarm-up (MailToaster), ramp-up, domain health checks, spam-rate monitoring, custom tracking domains, tracking controls, AI template scoring, and safe sending defaults
Required objectsA connected email account; DNS access for domain fixes and custom tracking links
SurfacesUI · REST API · MCP
Key limitRamp-up default: start at 10 emails per day, +3 daily, up to 100; warm-up seats follow your MailToaster plan
Stops on8% bounce rate stops the sending step until the next day (after 200 sends) — see Bounce handling
Does notGuarantee inbox placement; edit your DNS for you; rescue a burned domain quickly; monitor spam rates without a connected Postmaster account
PlansMailToaster warm-up is available with a paid Reply subscription — one warm-up seat per connected mailbox by default

Summary

Reply treats deliverability as infrastructure around every email account: MailToaster warm-up simulates positive email exchanges, ramp-up mode grows real sending volume gradually (on by default for new accounts), the Health Checker verifies the domain's SPF, DKIM, DMARC, MX, A, rDNS, and domain age weekly, the Spam Monitor pulls Google Postmaster spam-rate data, custom tracking links move opens, clicks, and opt-out URLs to your own domain, and an AI quality check scores every template before it sends. The background is explained in Email deliverability and Sender reputation.

Problems it solves

  • New mailboxes and domains burning out from full-volume cold sending on day one
  • Silent DNS misconfiguration — SPF, DKIM, DMARC errors surfaced with fixes instead of quiet spam-foldering
  • Compliance with Google's bulk-sender rules: authentication, one-click unsubscribe, spam rate below 0.3%
  • Spam-trigger templates and shared tracking domains dragging reputation down

What Reply can do

  • Warm up email accounts through MailToaster — no separate account, single sign-on from Reply, one warm-up seat per connected mailbox, workspace-scoped for teams
  • Apply warm-up profiles: New email account, Reputation protect, or a custom profile controlling what share of warm-up emails are opened, rescued from spam, replied to, or marked important
  • Grow warm-up volume by a fixed daily increment or a randomized daily range, with optional cleanup of warm-up emails older than 3 days from the Sent folder
  • Issue every warmed-up mailbox an Inbox filter — a unique ID on the account's Warm-Up page — that you paste into a Google Workspace filter or an Outlook rule so incoming peer-to-peer warm-up mail skips the inbox and files itself under a label or folder
  • Ramp up real sending automatically — on by default for new email accounts, starting at 10 emails per day and adding 3 per day until 100, stopping with a notification when the account's total limit is reached
  • Check domain health weekly on the Domain Setup tab — SPF, DKIM, DMARC, domain age, MX records, A records, and rDNS — with expandable errors and fix guidance
  • Monitor Gmail spam-report rates by connecting Google Postmaster Tools to the Spam Monitor tab
  • Replace Reply's default tracking domains with your own subdomains for opens, clicks, and opt-out links, matched to a sending domain, selected accounts, or all accounts
  • Disable open tracking in bulk across every sequence with one account-level toggle, with per-sequence overrides
  • Score email templates as you type on subject length, word count, question count, reading level, positivity, and spam-word count, with an overall response-likelihood recommendation
  • Space sends with randomized delays (default 300–450 seconds between emails on new accounts) and stop a sending step when the bounce rate crosses 8%

What Reply cannot do

  • Guarantee inbox placement — a 10/10 deliverability score does not promise inbox delivery
  • Edit DNS records for you — SPF, DKIM, DMARC, MX, and custom tracking CNAME/TXT records are set at your domain host
  • Skip the calendar: a new domain still needs roughly 2–3 weeks of warm correspondence before cold outreach (1–2 weeks for a new mailbox on an established domain)
  • Monitor spam rates without a Google Postmaster account connected for the domain
  • Analyze template text beyond 1,000 characters in the quality check
  • Warm up more mailboxes than your MailToaster seats allow — adding a mailbox with no free seat fails with a seat-count error

Required inputs

A connected email account; access to the domain's DNS for authentication fixes and custom tracking subdomains; a Google Postmaster account for spam monitoring; template text for quality scoring.

Produced outputs

Warm-up activity and progress per mailbox, a rising daily send ceiling per account, weekly domain health reports with per-record status, spam-rate dashboards, domain-based tracking URLs, and template scores with optimal-interval guidance.

Use Reply when

  • You are launching new mailboxes or domains and want warm-up, ramp-up, and monitoring in the same place sending happens — see Connect a mailbox
  • You need Google bulk-sender compliance visible: authentication status, unsubscribe mechanisms, spam-rate tracking
  • Multiple team mailboxes need consistent safety settings instead of per-rep improvisation

Do not use Reply when

  • You send transactional or newsletter volume — that calls for an ESP with dedicated IPs, not outreach-grade limits
  • A domain is already blocklisted and you need immediate recovery — reputation rebuilds over weeks; consider fresh sending domains while the damaged one rests

What you still need to build

  • The DNS changes themselves — Reply diagnoses and instructs; your domain host applies; see SPF, DKIM, DMARC
  • List hygiene policy — validation and targeting quality remain your call; see Data enrichment
capability: deliverability
supported: true
interfaces:
  product_ui: live
  api: live
  mcp: live
  cli: not-verified
required_objects:
  - email_account
side_effects:
  - sends_warmup_traffic
  - adjusts_sending_volume
human_approval_recommended: false

Limits

  • Ramp-up default: 10 emails per day at the start, +3 per day, up to 100; configurable per account
  • Default delay between emails on a new account: randomized 300–450 seconds
  • Bounce thresholds: warning at 4%, step stop at 8% after 200 daily sends — see Bounce handling
  • Google bulk-sender bar: spam rate below 0.3%, authentication required for high-volume senders, unsubscribe requests honored within two days
  • One SPF record per domain, maximum 10 DNS lookups; quality check reads up to 1,000 characters
  • Account daily ceilings: 400 per day on paid plans — see Limits

FAQ

What is the difference between warm-up and ramp-up?

Warm-up (via MailToaster) builds reputation with simulated positive exchanges — opens, replies, spam-folder rescues — outside your real sequences. Ramp-up runs inside Reply and gradually raises the real daily sending cap. Best practice: warm up first, keep warm-up running, and let ramp-up grow live volume — see Email warm-up.

How do I keep warm-up mail out of my real inbox?

Warm-up is peer-to-peer: once it is enabled, the mailbox both sends and receives warm-up email with other warm-up users, and that traffic lands in the inbox alongside real replies. Each connected account gets an Inbox filter — a unique ID shown in the upper right corner of the account's Warm-Up page under Email accounts. Copy it, then filter on it at the provider.

In Google Workspace, open Gmail Settings → See all settings → Filters and Blocked Addresses → Create a new filter, paste the ID into the Has the words field, click Create filter, and tick Skip the Inbox (Archive it), Apply the label (create a new label for it), and Also apply filter to 0 matching conversations. In Outlook, go to Settings → Filter → Rules → Add new rule, choose the condition Message body includes, paste the ID, pick or create a folder under Move to, and save. From then on warm-up email bypasses the inbox, and what is left there is real mail.

What does the Health Checker verify?

SPF, DKIM, DMARC, domain age, MX records, A records, and rDNS, refreshed weekly with notifications on problems. Each failed check expands into an explanation and a fix path — the records themselves are edited at your domain host. Background: SPF, DKIM, DMARC.

By default, tracking URLs use Reply's shared domains. Custom tracking links serve opens, clicks, and opt-out URLs from subdomains of your own domain (for example opens.yourdomain.com), tying tracking reputation to your domain instead of a shared one. Setup needs one CNAME and one TXT record per link.

Does disabling tracking help deliverability?

Removing tracking simplifies the email. Plain-text sending mode (default for new sequences) strips HTML, tracking, and images entirely, and the bulk toggle disables open tracking account-wide. You trade open-rate data for cleaner emails — see Email outreach.

Build with Reply