24/7 Global Monitoring

Uptime Monitoring That Never Sleeps

Monitor websites every 30 seconds from 4 global regions. Get instant alerts via email, SMS, Slack, or webhooks when something goes wrong.

Response Time

Performance over time

Last 24 hours

Average

186ms

Min

98ms

Max

312ms

🇺🇸Ashburn, Virginia

ASH

Response

200142ms

Last Check

Mar 10, 2026, 14:32:08 GMT-5

🇺🇸Portland, Oregon

PDX

Response

200189ms

Last Check

Mar 10, 2026, 14:32:06 GMT-5

🇩🇪Nuremberg, Germany

NBG

Response

200243ms

Last Check

Mar 10, 2026, 14:32:04 GMT-5

🇸🇬Singapore

SIN

Response

200312ms

Last Check

Mar 10, 2026, 14:32:02 GMT-5

Why Uptime Monitoring?

Catch downtime before your clients do

Your clients expect their websites to be online 24/7. When a site goes down, every minute of undetected downtime costs trust, revenue, and reputation. Sentinel checks your sites every 30 seconds and alerts you instantly.

30-second checks from 4 global regions
Multi-region verification prevents false alerts
Full incident history with response time data

30s

Check Interval

Global Regions

99.9%

Uptime SLA

2,880

Daily Checks per Monitor

Capabilities

Enterprise-grade monitoring, agency-friendly pricing

30-Second Checks

Industry-leading check frequency ensures you catch downtime fast—not minutes after your clients do.

Multi-Region Verification

Checks run from Ashburn, Portland, Nuremberg, and Singapore. We verify from multiple regions before alerting to prevent false positives.

Response Time Tracking

Track response times over time and spot performance degradation before it becomes full downtime.

Smart Notifications

Get alerts through email, SMS, Slack, Discord, Microsoft Teams, or webhooks. Configure per-monitor preferences.

Advanced HTTP Options

Custom HTTP methods, headers, request bodies, authentication, accepted status codes, and timeout configuration.

Domain & SSL Included

Every uptime monitor also tracks SSL certificate expiry and domain registration expiry automatically.

FAQ

Uptime monitoring questions

How often does Sentinel check my websites?

Uptime checks run as often as every 30 seconds. That means you find out about downtime fast, often before your clients notice anything is wrong.

Will I get false alarms when a site is actually up?

No. Checks run from four global regions and Sentinel uses consensus across those regions before alerting you, so a single flaky network path won't trigger a false positive.

How will I be notified when a site goes down?

Sentinel sends alerts via email, SMS, Slack, Discord, and webhooks. You can route notifications to wherever your team already works.

Can I monitor multiple client sites from one account?

Yes. Sentinel is built for agencies and freelancers managing many sites, so you can run uptime monitors across all of your clients from a single account.

What else can Sentinel monitor besides uptime?

Alongside uptime, Sentinel offers SSL certificate, DNS, domain expiration, keyword, JSON/API response assertion, ICMP ping, TCP port and heartbeat/cron checks, so you can cover a site's full health in one place.

Is there a free trial?

Yes. Paid plans include a 14-day free trial, there is also a free plan, and you can cancel anytime.

Get started in minutes

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