Setup, security, providers, the warmup loop and what the open Beta means. If something here doesn't cover it, drop us a line.
Getting started
Setup + warmup basics
How long does it take to warm up an inbox?
Your reputation starts building within ~24 hours. The standard ramp eases up over the first 4 weeks, most accounts reach a stable score around day 45 - 60. Brand-new domains can take a little longer for the final ESPs to settle.
Can I warm up a brand-new domain?
Yes — that's our main use case. Make sure SPF, DKIM and DMARC are configured first (our free tools generate the records for you).
What happens if my real campaign is sent during warmup?
Warmup sends are interleaved into your real schedule and stay under the ESP's daily cap. Heavy real-send days automatically slow the warmup back down.
Do I have to keep warmup running forever?
No — once your reputation stabilises you can switch to a light maintenance pace. Most users keep it on, since reputation can drift without it and the marginal cost is low.
Providers + integrations
Mailbox connection
Which mailboxes do you support?
Native Gmail API connector for Gmail, Google Workspace, and oAuth Microsoft 365 and personal Outlook. Standards-compliant SMTP + IMAP for any custom provider inbox— basically any inbox that can both send and receive messages.
Do I need to grant admin access for Workspace / M365?
No — per-user OAuth scopes only. We request access to a single mailbox at a time. No tenant-wide admin consent needed.
What if I'm on a custom mail server?
Use the SMTP + IMAP path. Detection by domain pre-fills the SMTP host. IMAP is needed too for receiving.
Pricing + billing
Plans during the Beta
Is it free right now?
Yes — while we're in open Beta, every plan is free for the first two months and no credit card is required to start. When Beta ends you can choose a paid plan or leave the warmup environment.
How will per-inbox pricing work after Beta?
Each connected mailbox counts as one inbox. A Basic plan with 5 inboxes would be the per-inbox price × 5. Annual billing saves 20%.
What unlocks the developer API?
The Pro plan adds rate-limited API access. The Max plan adds unlimited API + webhook subscriptions. Basic doesn't include API access.
What happens if I downgrade?
Your data is preserved. Pro-only features (custom templates, custom topics) revert to Basic defaults. Re-upgrade anytime to restore full access.
Security + privacy
Where your data lives
Where is my data hosted?
In the EU. Nothing leaves the EU — data residency is part of the design, not an add-on.
How are OAuth tokens + SMTP passwords stored?
Envelope-encrypted at rest. The plaintext secret only exists in memory while a worker uses it.
Can I export or delete my data?
Yes — right-to-export and right-to-delete are built in. Cancelling a workspace starts a grace window before anything is hard-deleted, and the audit log lets you export every state-changing event.
Are you GDPR-compliant?
Yes — designed for GDPR from day one. EU data residency, encryption at rest + in transit, and a DPA available on request.
Deliverability + warmup signal
Why this works
How is this different from sending to a list of seed mailboxes?
One-way seed-list sends are easy for ESPs to discount — the recipients never reply, never move out of spam, never mark as important. Our warmup builds those real engagement signals instead. We're growing this network out during Beta.
Will the AI content trip spam filters?
Every generated message is scored against a deliverability rubric before it sends — subject heuristics, link counts, sender patterns. Borderline content gets regenerated.
What if my reputation drops despite warmup?
The dashboard flags per-ESP divergence — one bucket dropping while others hold steady usually points at a content or technical issue. Recommendations point at the likely cause, and the inbox academy has playbooks.
Can I use it with my outreach tool (Lemlist, Smartlead, Instantly…)?
Yes — WarmupSleuth runs alongside any outreach platform. Connect the inbox to both; we coordinate sends to stay under the daily cap while your outreach tool handles campaigns.
Still have questions?
Email us — we read every message and reply within a business day.