Being in some warmup pools silently hurts your deliverability.

Trusting your warmup score by itself is a mistake — only a 3rd party can prove if you're at risk.

A sequencer can't independently verify its own pool quality. warm.ac is the 3rd party: public, free, live.

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Warmup ≠ warming

Deliverability problems you could not explain, until now. 3rd party analysis of 4 sequencers' warmup.

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Industry composition Your composition

See exactly which inboxes your sequencer sends you to. The real picture, not the industry average.

Public Data

Public data

Sampled from our own mailboxes, cross-referenced against 6M+ tracked domains — every major sequencer in one place.

  • Pool composition: Google, Microsoft, SMTP
  • Bounce rate per pool
  • Pool quality trends, week over week
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Private Data

Your composition

Your real warmup, measured directly — not the industry average. It's live right now, the moment you connect.

  • Your exact sub-pool composition
  • Your real Google representation
  • Pool drift alerts the moment it moves

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Warmup ≠ warming

Deliverability problems you could not explain, until now. 3rd party analysis of 4 sequencers' warmup.

This is huge.

We'll be back soon.