Uptime Monitoring

Fast, reliable uptime monitoring built for developers.

Monitor websites, applications, and infrastructure from 22+ global locations with up to 10 second check intervals. Checkly Uptime is the first layer of detection for issues impacting your end users.

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Checkly Uptime Monitoring Dashboard showing real-time status of multiple endpoints with response times and availability metrics

World-class engineering and SRE teams depend on Checkly to deliver reliable digital experiences

Vercel
Carhartt
CrowdStrike
Airbus
Fanatics
Mistral
ServiceNow
GoFundMe
Hopper
1Password
Fastly
Total Wine

The first layer of defense for your entire stack.

From simple URL uptime checks to complex heartbeat monitoring, Checkly has you covered with multi-protocol support for every layer of your tech stack.

URL Monitors

Check HTTP and HTTPS endpoints for status codes and response time across websites, APIs, docs, and product pages, and get alerted before SSL certificates expire.

URL Monitor configuration showing HTTP status checks and response time monitoring

TCP Monitors

Check database connections, mail servers, and any TCP service on a specific port. Confirm the port is open and responding, not just that the host is up.

TCP Monitor showing port connectivity checks for databases and services

ICMP Monitors

Ping any host or IP at the network layer to measure reachability, latency, and packet loss. No open port required.

ICMP Monitor configuration showing ping checks and host reachability monitoring

DNS Monitors

Resolve A, CNAME, MX, and other DNS records and assert the values you expect. Catch propagation and misconfiguration issues before they reach users.

DNS Monitor displaying domain resolution checks and DNS record validation

Heartbeat Monitors

Watch cron jobs, scheduled tasks, and batch processes. Checkly expects a ping on your schedule and alerts you when a job fails to run or finishes late.

Heartbeat Monitor showing cron job and scheduled task monitoring

Ensure availability & performance

Industry-leading monitoring frequency. Detect issues faster than any competitor with checks as frequent as every second.

Monitor close to your users

Run tests and monitors in 22+ global locations or inside your own infrastructure. Detect regional outages before they become global incidents.

Reduce false positives for maximum confidence

Smart retry logic and multi-location verification ensures you only get alerted when there's a real problem.

MONITORING AS CODE

Create and define monitors with the flexibility and scalability of code

Checkly is built for developers and modern SREs to take control of their application reliability with the flexibility and portability of code. Break through the challenges that a UI-first configuration has at scale with our CLI, Terraform, or Pulumi providers to define, manage, and deploy monitors right alongside your code.

  • Test and deploy your monitors in CI/CD
  • Automate thousands of monitors with a single command
  • Define templates and share code
  • Enable LLMs to manage Checkly for you
uptime.check.ts
1import { UrlMonitor, UrlAssertionBuilder } from 'checkly/constructs'
2
3new UrlMonitor('homepage-check', {
4 name: 'Homepage Monitor',
5 activated: true,
6 frequency: 60,
7 doubleCheck: true,
8 locations: ['us-east-1', 'eu-central-1'],
9 request: {
10 url: 'https://www.example.com',
11 assertions: [
12 UrlAssertionBuilder.statusCode().equals(200),
13 UrlAssertionBuilder.responseTime().lessThan(500),
14 ]
15 }
16})
HIGH-FREQUENCY

Detect critical availability issues in seconds, not minutes

Monitor your services near real-time with up to 1-second intervals, the fastest in the industry. Detect downtime faster, get alerts sooner, and resolve problems before your customers even are aware of the outage.

  • Check intervals from 1 second to 24 hours
  • Parallel execution across 22+ locations
  • Response time percentiles (P50, P95, P99)
  • Time to First Byte (TTFB) tracking
Uptime monitoring results showing response times and availability metrics
ALERTING

Reduce fatigue and increase confidence with alerting logic that cuts noise

Advanced retry logic ensures you only get alerted when there's a real problem affecting real customers. Configure confirmation checks, failure thresholds, and automatic retries.

  • Retry monitors from different regions
  • Configure custom thresholds based on time and frequency
  • Automatic retries reduce false positives
  • Reduce false alerts by up to 99%
alert-config.ts
1const alertConfig = {
2 retryStrategy: {
3 type: 'FIXED',
4 baseBackoffSeconds: 60,
5 sameRegion: true,
6 maxRetries: 5,
7 maxDurationSeconds: 300,
8 onlyOn: ['NETWORK_ERROR'],
9 },
10 alertSettings: {
11 escalationType: 'RUN_BASED',
12 runBasedEscalation: {
13 failedRunThreshold: 1,
14 },
15 },
16}

Monitor from where your users are

With 22+ data centers worldwide, detect regional issues before they become global outages. Get location-specific insights and understand performance from every corner of the globe.

Everything you need for a reliable digital experience

SSL Certificates Monitoring

Get alerts before certificates expire. Never let an expired cert take down your site.

Status Validation

Verify HTTP status codes (200, 404, 500) and ensure your endpoints return the expected responses.

Performance Validation

Set response time thresholds and track P50, P95, P99 percentiles for performance monitoring.

Monitoring Inside Private Networks

Deploy private agents to monitor internal services, staging environments, and VPN-protected resources.

Status Pages

Communicate service status to your users with public or private status pages powered by your monitors.

Multi-Protocol Support

Monitor HTTP, HTTPS, TCP, DNS, and ICMP endpoints from one platform.

CLI/Terraform Configuration

Manage your monitors as code with our CLI, Terraform provider, or Pulumi integration.

Incident Management

Integrate with PagerDuty, OpsGenie, FireHydrant, and Rootly for seamless incident response.

Integrates with your development and agentic workflow

Connect Checkly to your existing tools. Get alerts where your team already works and manage monitoring through your existing workflows.

Slack

Slack

Real-time alerts in your team channels with rich context and actionable details.

PagerDuty

PagerDuty

Trigger incidents and manage on-call rotations from PagerDuty.

OpsGenie

OpsGenie

Route alerts to the right team automatically based on your escalation policies.

Datadog

Datadog

Forward metrics to your observability platform for unified dashboards.

Grafana

Grafana

Visualize monitoring data in Grafana dashboards for comprehensive observability.

Discord

Discord

Get instant alerts in your Discord servers for real-time team notifications.

Coralogix

Coralogix

Stream monitoring data to Coralogix for advanced log analytics and insights.

Slack

Slack

Real-time alerts in your team channels with rich context and actionable details.

PagerDuty

PagerDuty

Trigger incidents and manage on-call rotations from PagerDuty.

OpsGenie

OpsGenie

Route alerts to the right team automatically based on your escalation policies.

Datadog

Datadog

Forward metrics to your observability platform for unified dashboards.

Grafana

Grafana

Visualize monitoring data in Grafana dashboards for comprehensive observability.

Discord

Discord

Get instant alerts in your Discord servers for real-time team notifications.

Coralogix

Coralogix

Stream monitoring data to Coralogix for advanced log analytics and insights.

Terraform

Terraform

Manage your monitoring infrastructure as code with our Terraform provider.

Honeycomb

Honeycomb

Send monitoring events to Honeycomb for deep observability and debugging.

Pulumi

Pulumi

Define monitors using your favorite programming language with Pulumi.

MS Teams

MS Teams

Receive alerts directly in Microsoft Teams channels where your team already works.

FireHydrant

FireHydrant

Trigger incidents in FireHydrant for streamlined incident management.

Rootly

Rootly

Connect to Rootly for automated incident response and resolution tracking.

Telegram

Telegram

Receive instant alerts via Telegram for mobile-first notifications.

Terraform

Terraform

Manage your monitoring infrastructure as code with our Terraform provider.

Honeycomb

Honeycomb

Send monitoring events to Honeycomb for deep observability and debugging.

Pulumi

Pulumi

Define monitors using your favorite programming language with Pulumi.

MS Teams

MS Teams

Receive alerts directly in Microsoft Teams channels where your team already works.

FireHydrant

FireHydrant

Trigger incidents in FireHydrant for streamlined incident management.

Rootly

Rootly

Connect to Rootly for automated incident response and resolution tracking.

Telegram

Telegram

Receive instant alerts via Telegram for mobile-first notifications.

Key facts

Uptime monitoring, in facts

What Checkly checks when it checks availability, where it checks from, and where availability stops being the right question.

Monitor types

URL, TCP, DNS, ICMP, gRPC, and heartbeat

Availability for public endpoints, network services, DNS records, host reachability, gRPC services, and scheduled jobs that fail silently.

Checkly uptime monitoring docs (opens in a new tab)

Where checks run

22 public locations, plus private locations

Running from at least two locations separates a real outage from a problem at one vantage point. Private locations reach services inside your network.

Checkly locations docs (opens in a new tab)

What it proves

The endpoint answered, and answered correctly

URL monitors assert on status and response time, so a slow endpoint is a distinct signal from a dead one.

Checkly uptime monitoring docs (opens in a new tab)

Silent failures

Heartbeat monitors for cron jobs and workers

A job that stops running has no endpoint to poll. A heartbeat monitor alerts when the expected check-in does not arrive.

Checkly uptime monitoring docs (opens in a new tab)

How monitors are managed

TypeScript, Terraform, or Pulumi in Git

Uptime monitors are defined in the same code workflow as browser and API checks, and share alert channels with them.

Checkly monitoring as code docs (opens in a new tab)Checkly CLI docs (opens in a new tab)

What it does not prove

That the user journey still works

A login page can return 200 while login is broken. Use a Playwright browser check when the workflow, not the endpoint, is the thing that matters.

Checkly browser check docs (opens in a new tab)

Facts checked . Vendor pricing and feature pages change without notice, so verify anything decision-critical against the linked source.

Fit check

Is uptime monitoring the right check for this?

Checkly is a strong fit when

  • You need to know quickly that a public endpoint, port, or DNS record stopped responding.
  • You have scheduled jobs or workers that currently fail without anyone finding out.
  • You want availability checks in the same code workflow and alert routing as your deeper checks.

Checkly may not be the best fit when

  • The thing you need to verify is a multi-step workflow such as login, search, or checkout. Use a browser check instead.
  • You need performance data from real user traffic. That is real user monitoring, which Checkly does not do.
  • A single ping from as many countries as possible is the whole requirement and depth of check does not matter.

Frequently asked questions

Everything you need to know about Checkly uptime monitoring.

Uptime monitoring continuously checks whether your websites, APIs, and infrastructure are reachable and responding correctly from outside your network. Checks run on a fixed schedule from multiple global locations, verify each response, and alert your team the moment one fails, so you find out before your users do.

Checkly runs URL/HTTP, TCP, ICMP (ping), DNS, and heartbeat monitors, plus Playwright-based synthetic checks and API checks. You can watch public endpoints, individual ports, DNS records, SSL certificates, and scheduled jobs, all defined in one place as code.

Checkly runs checks as often as every 10 seconds from 22+ global locations, with 1-second intervals available on request. Multi-location confirmation catches most availability issues within seconds and verifies them across regions before alerting, so detection stays fast without false alarms.

Uptime percentages cap how much downtime is allowed over a period. 99.9% ("three nines") permits about 43 minutes of downtime per month, 99.99% about 4 minutes, and 99.999% ("five nines") about 26 seconds. Uptime monitoring measures your real availability against the SLA you promise.

Checkly confirms failures from multiple locations before alerting, with configurable retries, thresholds, and maintenance windows. Alerts route through Slack, PagerDuty, Opsgenie, and webhooks with escalation logic, so on-call only hears about incidents that are real.

Yes. Alongside 22+ public locations, Checkly supports private locations, so you can monitor internal APIs, staging environments, and services that are not exposed to the public internet, using the same monitoring-as-code workflow.

Uptime monitoring answers "is it up and responding?" with lightweight, high-frequency checks like HTTP, TCP, ICMP, and DNS. Synthetic monitoring runs full Playwright scripts through real user flows such as login or checkout. Checkly does both, so you can start with uptime and add deeper checks later.

You define monitors in TypeScript or JavaScript with the Checkly CLI, or use the Terraform and Pulumi providers. Version your monitoring configuration, review changes in pull requests, and deploy through your CI/CD pipeline like any other code.

Start monitoring in minutes

Catch issues early across your entire digital footprint. Reduce risk and MTTR with reliable uptime monitoring from Checkly.

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