Last updated: August 2025

Looking for a Mimecast DMARC Analyzer alternative that enables you to rapidly and confidently take control of email authentication? Red Sift OnDMARC is built to help organizations detect and stop unauthorized use of their domains—efficiently and safely. Here's how the two products compare.

Red Sift OnDMARC is a fully cloud-based DMARC application designed to simplify and accelerate the deployment of DMARC, SPF, DKIM, BIMI and MTA-STS. By removing the complexity of manual configuration, it helps teams move quickly from implementation to enforcement, often achieving full protection within 6–8 weeks.

Notable differentiators include:

• Integrated BIMI and Verified Mark Certificate (VMC) support to unlock brand visibility in the inbox.
• An embedded LLM-powered assistant that provides clear, actionable guidance to troubleshoot and fix issues.
• DNS monitoring tools that surface risks such as dangling DNS records or subdomain hijacking.

OnDMARC is trusted by enterprises worldwide, with customers such as Capgemini, Domino’s, Wise, and ZoomInfo, and since 2023 has also been integrated into Cisco’s Domain Protection portfolio.

A 14-day trial with full access to all features is available directly from the Red Sift website.

DMARC Analyzer, originally founded in 2012 and acquired by Mimecast in 2019, is one of the more established offerings in this space. Mimecast itself is widely recognized for its Secure Email Gateway (SEG).

The product helps organizations monitor and configure the core authentication standards DMARC, SPF, DKIM. While a 14-day trial is available, it does not provide access to all enterprise-level functionality. Features such as forensic reporting and SPF delegation require a full subscription and could not be tested as part of this review. However, where possible, we have referenced Mimecast’s knowledge base and public resources to understand what the paid version offers.

While Red Sift OnDMARC and DMARC Analyzer are both designed to help security teams take control of their email-sending services and protect their domains from exact domain impersonation, their key differences lie in their target audiences, feature sets, speed to enforcement, and wider portfolio.

Let’s get into the nitty-gritty of how these two applications compare 👇

Implementing DMARC can be a complex and error-prone process, which makes intuitive technology and smooth provisioning critical for success.

OnDMARC delivers a guided onboarding experience from the moment a trial is activated. The ‘My Domains’ dashboard immediately displays each domain alongside the status of its protocols (DMARC, SPF, MTA-STS, BIMI), giving teams clarity from the outset.

Domain protection begins with a simple three-step workflow. Customers can either manage records directly or use Red Sift’s Dynamic Services, which streamlines setup by replacing direct DNS editing with a handful of intelligent records. This reduces manual effort and minimizes the chance of misconfiguration.

Once the records are active, DMARC reports start flowing quickly, providing visibility and a clear path to enforcement.

OnDMARC includes the Investigate tool, which allows real-time testing of authentication settings, removing the 24-hour wait typically required for DMARC reports to propagate. This enables faster troubleshooting and speeds up policy deployment.

Investigate connects directly with the Email Sources inventory, so users can pinpoint issues with SPF or DKIM alignment, view active selectors and mechanisms, and validate fixes instantly.

The tool also incorporates Compliance Profiles, helping organizations check their configuration against standards such as the UK Minimum Cyber Security Standard, US Binding Operational Directive 18-01, and bulk sender requirements from Google, Yahoo, and Microsoft.

The Email Sources view creates a live, categorized map of all services observed sending on behalf of a domain. Teams can tag sources as trusted or suspicious, link associated SPF and DKIM details, and capture ownership information for continuity.

This prevents duplication of effort and ensures critical knowledge isn’t lost across staff changes.

DMARC Analyzer provides a setup wizard to guide initial configuration, including options for enabling forensic reports. Domains and domain groups can be added, and once a DMARC record is published, reports begin to appear within 72 hours.

A “Guide” section in the main menu provides short in-app tours for navigating report analysis and forensic report review. It’s useful that reports can be broken down by sending source, result, organization, or host.

DMARC Analyzer includes protocol-specific checkers for DMARC, SPF, DKIM, and BIMI. However, we did not find an integrated diagnostics tool for end-to-end troubleshooting across protocols.

Unlike OnDMARC, DMARC Analyzer does not automatically compile an inventory of all observed sending services. While the SPF Delegation feature allows users to manually label services and SPF mechanisms, this approach requires more manual oversight, particularly for organizations with complex or large domain portfolios.

Managing DNS records for SPF, DKIM, DMARC, and MTA-STS can be challenging, especially when multiple domains and registrars are involved. Manual edits are often error-prone and difficult to maintain at scale.

OnDMARC addresses this with Dynamic Services, which allows administrators to manage all records directly within the application instead of making manual DNS changes. Static DNS entries are replaced with smart records—applied through NS delegation for DKIM and DMARC, or a smart TXT record for SPF.

With Dynamic Services, users can:

• Adjust DMARC policies without editing DNS.
• Add or remove SPF mechanisms easily.
• Deploy 2048-bit DKIM keys, even where DNS providers don’t support them.

This approach reduces friction, prevents mistakes, and makes ongoing record management significantly more efficient.

DMARC Analyzer does not provide hosted record management for DKIM or DMARC. Record updates must be made directly in DNS, which can slow down implementation and increase the chance of misconfiguration. However, it does offer hosted SPF as part of its SPF Delegation feature.

With OnDMARC’s Dynamic SPF, all authentication records (SPF, DKIM, DMARC, MTA-STS) can be managed from the app once smart records are in place. After delegation, updates no longer require DNS access.

Dynamic SPF consolidates all authorized services into a single include, bypassing the 10-lookup limit without resorting to macros—avoiding compatibility issues with older systems.

SPF delegation is not available during the trial, but Mimecast documentation shows that it is included on paid tiers via the DNS Manager.

Mail Transfer Agent Strict Transport Security (MTA-STS) ensures the secure transmission of emails over an encrypted SMTP connection and stops man-in-the-middle (MITM) attacks. 

OnDMARC includes hosted MTA-STS as part of its Dynamic Services. This covers policy hosting, certificate lifecycle management, and TLS reporting in one place. Any TLS violations or downgrade attempts are surfaced automatically, giving security teams immediate visibility into encryption gaps and potential MITM attempts.

DMARC Analyzer does not provide support for MTA-STS or TLS-RPT protocols.

Brand Indicators for Message Identification (BIMI) allows organizations to display their verified brand logo next to DMARC-authenticated emails. Studies have shown BIMI can lift open rates by nearly 40% and improve brand recall by more than 40%.

OnDMARC is the only DMARC solution on the market with a fully integrated BIMI + Verified Mark Certificate (VMC) workflow. It streamlines the entire process, from application to issuance, without requiring customers to interact directly with a Certificate Authority.

Through a direct API integration with DigiCert—the CA that issues VMCs—Red Sift securely transfers application data, processes the request, and issues the certificate, making domains BIMI-ready faster. Red Sift is the only vendor using DigiCert’s API for this purpose.

For enterprise customers, OnDMARC also includes a complimentary VMC license, eliminating the need to allocate extra budget for BIMI adoption.

DMARC Analyzer provides a BIMI Checker tool within its product and on its website. However, it does not currently offer hosted BIMI or integrated certificate management.

Most DMARC solutions focus narrowly on email authentication, leaving DNS blind spots unaddressed. With the rise of SubdoMailing attacks—where adversaries abuse abandoned or misconfigured subdomains to send authenticated spam—having visibility into DNS configuration has become an essential layer of protection.

OnDMARC incorporates DNS Guardian, which continuously monitors for DNS misconfigurations and domain takeover attempts. It can detect issues such as dangling DNS records, CNAME hijacking, and signs of SubdoMailing campaigns. This capability is powered by Red Sift ASM’s asset intelligence and DNS expertise, providing a level of visibility not currently offered by other DMARC vendors.

DMARC Analyzer does not include functionality to detect dangling records or SubdoMailing risks. Its DNS Timeline feature tracks changes to DNS records such as SPF, DKIM, and DMARC over time, but it is not designed for misconfiguration monitoring.

LLMs and AI assistants like GPT-4 are increasingly recognized as valuable for troubleshooting and accelerating workflows. In security, however, the challenge is that generic models are rarely embedded within tools or trained on the right domain knowledge, limiting their usefulness. Integrating this technology directly into security products can deliver meaningful efficiency gains for teams.

OnDMARC features Radar, a domain-focused LLM assistant built directly into the platform. Radar identifies misconfigurations, highlights errors, and provides step-by-step guidance across the DMARC ecosystem. By streamlining issue triage and offering practical recommendations, it helps teams reach full enforcement faster—even if users are less technical.

At the time of writing, DMARC Analyzer does not provide an AI or LLM assistant.

Effective alerting ensures that organizations can respond quickly to emerging risks, reducing the chance that phishing or misconfigurations slip through unnoticed.

OnDMARC includes a Notifications feature that delivers daily or weekly reports and real-time alerts to email or Slack, depending on user preference. These include:

• Compliance Reports – summarize volumes of passed, quarantined, and rejected mail across selected domains.
• Action Reminders – list outstanding configuration steps for domains.
• Configuration Alerts – flag when services with poor reputations send on behalf of your domain, when new senders appear, or when compliance levels drop sharply (a sign of misconfiguration).

DMARC Analyzer provides alerting options such as:

• DNS Monitor – emails triggered by DNS changes (invalid SPF, new DKIM keys, etc.).
• DMARC Summary – volume and compliance updates.
• Compliance Monitor – real-time monitoring of compliance thresholds.

These alerting features are only available in premium subscription tiers.

Time-to-enforcement is one of the most important measures of a DMARC deployment. Expert guidance can make a major difference in helping organizations reach protection quickly while reducing risk.

At the Enterprise tier, OnDMARC provides access to a dedicated Customer Success Engineering (CSE) team with deep expertise in DMARC, SPF, and DKIM. These engineers partner closely with customers to support complex rollouts and accelerate safe progress to enforcement.

The CSE team consistently receives strong feedback, with NPS scores of 62 and CSAT of 88, and has supported major brands such as Capgemini, ZoomInfo, TalkTalk, and Holland & Barrett. OnDMARC’s customer satisfaction is also reflected in market recognition: it has been repeatedly ranked a DMARC Leader on G2, and was named the #1 DMARC vendor in Europe in Summer 2025.

Mimecast offers three support tiers—Basic, Advanced, and Premium. Access to a Technical Account Manager is included only at the Premium level.

Feedback on Mimecast’s customer support is generally positive, although there is limited public commentary available. The most recent review of DMARC Analyzer on G2 dates back to 2024.

OnDMARC provides a documented REST API for connecting into custom dashboards, reporting environments, or internal systems. Key capabilities include managing Dynamic Services, programmatically analyzing domains, creating custom charts from reporting data, configuring alerts, and adding or removing domains. Working examples are included in the documentation to help teams get started quickly.

DMARC Analyzer also includes a comprehensive API set with detailed documentation to support integration into third-party workflows and external systems.

OnDMARC benefits from multiple external data integrations to strengthen detection and forensics. This includes:

• A Spamhaus feed, flagging malicious sources and improving deliverability insights.
• An integration with Validity, adding intelligence around brand spoofing and phishing activity.
• Exclusive access (shared by only two DMARC vendors) to the Yahoo forensics feed, enriching forensic reports.
• A unique partnership with Abusix to further enhance forensic capabilities.

In 2025, Red Sift also introduced the Event Hub, enabling teams to stream real-time structured security events from Red Sift products into SIEMs, SOARs, XDRs, ticketing tools, messaging platforms, and cloud storage solutions.

As part of the Red Sift Pulse Platform, OnDMARC works seamlessly with other applications such as Brand Trust, automatically syncing domain assets to monitor for impersonation and lookalike activity.

DMARC Analyzer sits within Mimecast’s product suite. For brand protection, Mimecast offers Brand Exploit Protect, which covers lookalike domain detection. This capability was added through Mimecast’s acquisition of Segasec. As DMARC Analyzer and Brand Exploit Protect originated from separate acquisitions, it is not clear whether the two products are fully interoperable.

Unlike OnDMARC, DMARC Analyzer does not integrate third-party data feeds for forensic enhancement and does not currently provide SIEM integrations.

Both Red Sift OnDMARC and Mimecast DMARC Analyzer help organizations implement and manage DMARC, SPF, DKIM, and MTA-STS. Each offers automation, reporting, and API access, making them credible choices for improving domain security.

The decision comes down to scope and priorities:

• Mimecast DMARC Analyzer provides a straightforward DMARC tool that may be sufficient for self-service teams or enterprises willing to invest in managed services.
• Red Sift OnDMARC extends well beyond DMARC basics, offering embedded AI assistance, DNS configuration monitoring, deep ecosystem integrations, and event streaming capabilities. For organizations that want to move quickly, reduce manual overhead, and scale protection intelligently, OnDMARC delivers a more advanced and future-ready solution.