Top 7 DNS Monitoring Tools Compared

Choosing a DNS monitoring tool requires understanding what you are monitoring for. Some tools focus on availability (is your DNS resolving?), others on change detection (did someone modify your records?), and a few cover both plus domain registration health.

This comparison reviews seven options across the spectrum, from dedicated DNS monitoring platforms to broader infrastructure tools with DNS capabilities.

For background on why DNS monitoring matters and what records to track, see our introduction to DNS monitoring and our guide on monitoring DNS changes and detecting hijacking.

What Differentiates DNS Monitoring Tools

Before the comparison, here are the key capabilities to evaluate:

• Record change detection -- continuous polling with baseline diffing, not just point-in-time checks
• Severity classification -- distinguishing critical changes (NS, MX) from routine ones (SOA serial increments)
• CDN/dynamic IP awareness -- suppressing false positives from providers like Cloudflare that rotate IPs
• Per-record-type configuration -- ability to choose which record types to monitor
• Domain registration monitoring -- expiry alerts and EPP status tracking via WHOIS or RDAP
• Alerting integrations -- Slack, PagerDuty, email, webhooks
• Propagation checking -- querying multiple resolvers worldwide

The 7 Best DNS Monitoring Tools

1. Metric Tower

Metric Tower provides DNS change detection as part of its broader security monitoring platform. It takes a security-first approach: establishing a baseline of your DNS records on the first check, then diffing every subsequent check to detect unauthorized modifications.

What it monitors: All DNS record types (A, AAAA, MX, NS, TXT, CNAME, CAA, SRV, SOA, PTR) with per-record-type toggles. Automatic CDN provider detection (Cloudflare, Akamai, Fastly) suppresses false positives from expected IP rotation. Changes are classified by severity: NS/A/MX changes are critical, SPF weakening and DMARC removal are high, CAA/SRV/TXT are medium. Domain registration monitoring via RDAP tracks expiry dates and critical EPP status changes (pendingDelete, serverHold, pendingTransfer, redemptionPeriod).

Pros:

• Severity-based change classification -- prioritizes critical alerts over noise
• CDN-aware monitoring that avoids false positives from Cloudflare/Akamai IP rotation
• Per-record-type configuration so you control what triggers alerts
• RDAP-based domain registration monitoring with EPP status change alerts
• Unified platform -- DNS alongside SSL, uptime, and vulnerability scanning
• Multi-channel alerting: Slack, Teams, PagerDuty, OpsGenie, email, webhooks

Cons:

• Does not yet support per-nameserver comparison (querying each authoritative NS individually)
• Broader security platform may be more than teams need for DNS-only monitoring

Pricing: Free tier available. Pro, Business, and Enterprise plans -- see pricing page for current rates.

2. DNSspy

DNSspy is a dedicated DNS monitoring service that focuses specifically on zone file tracking and record change detection. It checks your DNS records from multiple global locations and alerts when changes are detected.

Pros:

• Purpose-built for DNS monitoring with a focused feature set
• Zone file tracking with historical change log
• Checks from multiple geographic locations for propagation monitoring
• DNSSEC validation monitoring
• Domain expiry tracking

Cons:

• Limited to DNS monitoring -- no SSL, uptime, or security scanning integration
• Smaller user base compared to broader monitoring platforms
• Limited alerting integrations compared to general-purpose tools

Pricing: Free for a limited number of domains. Paid plans for larger domain portfolios. As of early 2026.

3. Datadog

Datadog offers DNS monitoring as part of its Network Performance Monitoring and Synthetic Monitoring products. For enterprises already invested in the Datadog ecosystem, adding DNS monitoring is a natural extension.

Pros:

• Deep integration with existing Datadog infrastructure, APM, and log monitoring
• DNS resolution time tracking and anomaly detection
• Global check locations via Synthetic Monitoring
• Powerful alerting with composite monitors and conditional logic
• Excellent visualization and dashboarding

Cons:

• Expensive -- DNS monitoring requires Network Performance Monitoring ($5/host/month) or Synthetic Monitoring ($5 per 10K runs)
• No dedicated DNS change detection with severity classification -- you build this yourself with monitors
• Overkill for teams that only need DNS monitoring without the full observability stack
• Complex pricing model makes cost estimation difficult

Pricing: Network Performance Monitoring from approximately $5/host/month. Synthetic Monitoring from approximately $5 per 10K test runs. Total cost depends on infrastructure size. As of early 2026.

4. ThousandEyes (Cisco)

ThousandEyes provides network intelligence with DNS monitoring as part of its internet visibility platform. It monitors DNS resolution performance across the global internet, making it well-suited for enterprises that need to understand DNS behavior from the end-user perspective.

Pros:

• Comprehensive network path analysis -- traces DNS queries across the internet infrastructure
• Global vantage points for monitoring DNS resolution from diverse locations
• Detects DNS hijacking, cache poisoning, and resolution latency issues
• Strong BGP monitoring integration (relevant for BGP-DNS combined attacks)
• Excellent for multi-region and CDN-heavy architectures

Cons:

• Enterprise-focused pricing -- significantly more expensive than dedicated DNS tools
• Complex platform with a steep learning curve
• More focused on availability and performance than record change detection
• Requires Cisco sales engagement for pricing

Pricing: Enterprise pricing on request. Generally positioned for organizations with significant infrastructure budgets. As of early 2026.

5. Pingdom (SolarWinds)

Pingdom, now part of SolarWinds, offers DNS monitoring alongside its well-known uptime and page speed monitoring. It checks DNS resolution from global probe servers and alerts on failures or slow responses.

Pros:

• Established brand with a long track record in uptime monitoring
• DNS resolution monitoring from multiple global locations
• Bundled with uptime, transaction, and page speed monitoring
• Good integration ecosystem (Slack, PagerDuty, email, webhooks)
• Straightforward pricing compared to enterprise alternatives

Cons:

• DNS monitoring focuses on availability (does it resolve?) rather than change detection (did the record change?)
• No DNS record change baseline or diffing
• No severity classification for different record types
• SolarWinds brand suffered reputational damage after the 2020 supply chain attack (though Pingdom was not directly affected)

Pricing: Starts at approximately $15/month for 10 uptime checks with DNS monitoring included. As of early 2026.

6. MxToolbox

MxToolbox is a long-standing DNS health and email deliverability platform. It provides free DNS lookup tools alongside paid monitoring that tracks MX records, blacklist status, and email authentication records (SPF, DKIM, DMARC).

Pros:

• Strong email-focused DNS monitoring (MX, SPF, DKIM, DMARC)
• Free lookup tools for ad-hoc DNS, MX, and blacklist checks
• Blacklist monitoring across 100+ DNS-based blocklists
• Email deliverability diagnostics and SMTP testing
• Well-known in the email administration community

Cons:

• Primarily email-focused -- A, AAAA, NS, CAA, and SRV monitoring is secondary
• Free tier is limited to basic lookups; monitoring requires paid plans
• Interface can feel cluttered compared to modern monitoring tools
• No CDN-aware suppression for dynamic IP providers

Pricing: Free for basic lookups. Delivery Center plans start at approximately $129/month for monitoring. As of early 2026.

7. DNS Checker (dnschecker.org)

DNS Checker is a free web-based tool for checking DNS propagation across global resolvers. It is not a monitoring service in the traditional sense -- it does not run scheduled checks or send alerts -- but it is useful for manual propagation verification.

Pros:

• Completely free with no account required
• Checks DNS propagation across 20+ global resolvers simultaneously
• Supports all record types (A, AAAA, MX, NS, TXT, CNAME, SOA, CAA, SRV)
• Simple, fast interface for quick checks

Cons:

• Not a monitoring tool -- no scheduled checks, no alerts, no baseline tracking
• Manual-only: you have to visit the site and run the check yourself
• No change detection, severity classification, or historical data
• Useful for troubleshooting, not for continuous security monitoring

Pricing: Free. No paid tiers.

How to Choose the Right DNS Monitoring Tool

Your choice depends on what you are protecting against and what infrastructure you already have.

You need DNS change detection for security. Choose Metric Tower or DNSspy. Both focus on detecting unauthorized record modifications rather than just availability. Metric Tower adds severity classification, CDN awareness, and RDAP-based domain registration monitoring.

You are an enterprise with existing Datadog or Cisco infrastructure. Add DNS monitoring through your existing platform. The marginal cost of adding DNS monitoring to Datadog or ThousandEyes is justified if you are already paying for the platform and want consolidated alerting.

You primarily care about email deliverability. MxToolbox is purpose-built for email DNS health. It monitors MX records, blacklists, and email authentication records better than general-purpose DNS tools.

You need uptime + DNS monitoring on a budget. Pingdom bundles DNS resolution checks with uptime monitoring at a competitive price point. It will tell you if DNS stops resolving but will not detect subtle record changes.

You need a quick propagation check right now. DNS Checker is free, instant, and requires no account. Use it for ad-hoc troubleshooting, but do not rely on it as your monitoring strategy.

Summary Comparison Table

Tool	Change Detection	Severity Classification	CDN-Aware	Domain Expiry	Free Tier
Metric Tower	Yes (baseline diffing)	Yes (4 levels)	Yes	Yes (RDAP + EPP)	Yes
DNSspy	Yes (zone tracking)	Basic	No	Yes	Limited
Datadog	DIY (build monitors)	DIY	No	No	No
ThousandEyes	Partial	No	Yes (network-aware)	No	No
Pingdom	No (availability only)	No	No	No	No
MxToolbox	Partial (email records)	No	No	Yes (WHOIS)	Lookups only
DNS Checker	No	No	No	No	Yes (fully free)

Combining DNS Monitoring with SSL and Uptime

DNS monitoring is most valuable when combined with SSL certificate monitoring and uptime checks. A DNS hijacking attack often involves obtaining a new SSL certificate for the hijacked domain (using DNS-based domain validation), so monitoring both DNS records and Certificate Transparency logs provides defense in depth.

Metric Tower's DNS monitoring integrates with SSL monitoring and uptime checks in a single platform, giving security teams a consolidated view of domain health. For teams evaluating their SSL monitoring options alongside DNS, see our comparison of SSL monitoring tools.