AcornDMARC vs Postmark DMARC

What Postmark DMARC does

Postmark offers a free DMARC monitoring service at dmarc.postmarkapp.com. You point your DMARC RUA to Postmark and receive a weekly email digest summarizing your DMARC data. The digest shows pass/fail percentages and lists the sources that sent email as your domain.

Postmark DMARC is a solid starting point. It is free, easy to set up, and gives you visibility into DMARC that you would not have otherwise. For many people, the weekly digest is enough.

Where Postmark DMARC falls short

No persistent dashboard

Postmark DMARC sends a weekly email. There is no web dashboard where you can log in and see your data. If you delete the email or want to look at data from three weeks ago, it is gone. You cannot drill into specific senders, filter by time period, or track trends over time.

No per-record data

The weekly digest aggregates everything into summary percentages. You see that 95% of email passed DMARC, but you cannot see which specific IP addresses failed, how many messages each source sent, or what the disposition was for each source. This per-record detail is what you need to diagnose and fix alignment issues.

No issue detection

Postmark tells you what happened. It does not tell you what to do about it. When a sender fails DMARC, you need to know: is this a legitimate service that is misconfigured, or is someone spoofing your domain? Postmark's digest does not categorize or prioritize issues.

Weekly cadence only

Reports arrive weekly. If something breaks on Monday, you do not find out until the following week. For domains with active email traffic, a week is too long to wait.

What AcornDMARC does differently

Real-time dashboard

AcornDMARC gives you a web dashboard that updates as reports arrive. You see pass rates, sender breakdowns, SPF/DKIM alignment, and disposition trends across any time period. The data is always there when you need it.

Per-record detail

Every record from every aggregate report is stored and queryable. You can see exactly which IP sent how many messages, whether they passed or failed each check, and what action was taken. This is the data you need to identify misconfigurations and spoofing attempts.

Issue detection and categorization

AcornDMARC automatically categorizes issues by severity: hard DMARC failures (both SPF and DKIM fail), SPF-only failures (passes DMARC but fragile), and DKIM-only failures. Each issue includes context about the sender and recommended actions.

Multi-domain support

If you manage multiple domains, AcornDMARC shows all of them in one dashboard. Postmark requires a separate RUA setup for each domain and sends separate weekly emails for each.

Pricing comparison

Postmark DMARC is free. AcornDMARC is also free. The difference is in what you get: Postmark gives you a weekly summary email. AcornDMARC gives you a persistent dashboard with full data, issue detection, and weekly summary emails.

Who should use which

If you send transactional email through Postmark and just want basic DMARC visibility, Postmark's built-in monitoring is convenient since you are already using their service. If you want per-sender detail, a dashboard you can revisit, issue categorization, or you manage multiple domains, AcornDMARC is the better fit.