Website Connectivity Diagnostics API

A simple API for DNS, TCP, TLS, and HTTPS health checks built for developers.

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JSON or Prometheus Output Regions: US · EU · APAC Free To Start: No Credit Card Needed OpenAPI 3.0
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Website Health Check

Comprehensive diagnostics in a single pass.

Latency

Global ping response times.

DNS Resolve

Verify A and AAAA records.

HTTP Request

Inspect status codes and headers.

TLS Cert Active

Validate certificate chain and expiry.

Simple, transparent pricing

Start free with 2,000 checks/month. Scale as you grow.

Free

$0/mo

2,000 checks/month

  • 10 req/min
  • Multi-region checks
  • Quorum consensus
Starter

$19/mo

25,000 checks/month

  • 60 req/min
  • Observations enabled
  • Problem detection
Popular
Pro

$29/mo

150,000 checks/month

  • 300 req/min
  • Full observations
  • AI-powered insights
See all plans

How it works

1

Send a host

Pass a domain or IP address. Just the hostname like example.com or 192.0.2.1.

2

Checks run from 3 regions

US, EU, and APAC execute DNS, Ping, TLS, and HTTP checks in parallel.

3

Results are aggregated with quorum

You get a single status even if one region behaves differently. 2 out of 3 = quorum met.

4

Get one unified JSON response

Includes overall status, per-region details, latency, DNS, TLS info, and HTTP results. Prometheus format also available.

Use cases

Synthetic monitoring

Call from your cron jobs, CI/CD, or monitoring stack. Detect outages before your users do with multi-region visibility.

Pre-deployment verification

Confirm DNS propagation and TLS setup before launch. Verify your changes are live across all regions.

Incident investigation

Get per-region evidence to debug outages. Pinpoint whether issues are global or localized to specific regions.

Best for: DevOps, SRE teams, CI/CD pipelines, and monitoring systems

FAQ

What checks does NetDiag perform?
NetDiag performs four types of checks: DNS (A/AAAA record resolution), Ping (ICMP with TCP fallback), TLS (certificate validity, expiry, issuer, protocol), and HTTP (status code, response time, final host after redirects). All checks run from multiple regions simultaneously.
What does "multi-region" mean?
Every check runs from three geographic locations: US (Hillsboro), EU (Falkenstein), and APAC (Singapore). This catches issues that only affect specific regions, like CDN edge problems, geo-routing misconfigurations, or DNS propagation delays.
What is quorum and why does it matter?
Quorum aggregates results across regions. If 2 out of 3 regions report the same status, that becomes the consensus result. This helps you distinguish between "one region is flaky" vs "the service is actually down" without manually comparing per-region data.
Do you support custom DNS servers?
Yes. Use the dns query parameter to specify a custom DNS server (IPv4, IPv6, or hostname). For example: ?host=example.com&dns=8.8.8.8. If not specified, each region uses its default resolver.
Can I run only specific checks?
Yes. Use the checks query parameter to specify which checks to run. For example: ?host=example.com&checks=dns,tls runs only DNS and TLS checks.
What output formats are available?
NetDiag returns results in JSON by default. You can also request Prometheus format for direct integration with monitoring systems using the Accept: text/plain header.
How are rate limits calculated?
Rate limits are per API key, measured in requests per minute. Free tier: 10 req/min. Starter: 60 req/min. Pro: 300 req/min. Monthly check run quotas are counted separately from rate limits.
Do you store my traffic or certificate data?
NetDiag returns metadata needed for diagnostics (status, latency, expiry dates, etc.). We don't intercept actual traffic or store private keys. For detailed data handling, see /privacy.

Ready to get started?

Start with the free plan. No credit card required.

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