¿Vale la pena el monitoreo de sitio gratis? Comparativa honesta

There are dozens of site-monitoring services on the market. Almost all have a free tier. The reasonable question: is free enough?

The honest answer: it depends on what you're protecting. For a personal portfolio, it's enough. For anything that generates revenue, no. Let's break down where the line is.

What every free version does well

The popular tools — UptimeRobot, Better Stack, StatusCake, HetrixTools, Sentinela — all offer in the free tier:

• HTTP check every 5 minutes (some every 1 minute)
• 5 to 50 monitors
• Email alert
• Basic public status page
• 30 to 90 days of uptime history

For a blog, landing page, or portfolio? It's great. You don't need to pay anything.

Where free starts to hurt

1. The check interval is too high

The free-tier standard is 5 minutes. That means if the site goes down at 2:01 PM, you're only warned at 2:06 PM.

For e-commerce during business hours, 5 minutes is enough to lose orders. For an API that other systems consume, 5 minutes is enough for the customer to complain first. For serious production, you want 1 minute.

2. It only checks from a single place

Free versions usually check from a single data center — almost always in the US or Europe. Problems:

• If the AWS route to the US goes down but your server is in Brazil, the monitor reports "down" and your Brazilian customers are accessing it fine. False positive.
• If your Brazilian provider has bad peering with your customers' carrier, the monitor says "up" and the customer says "slow/down". False negative.

For serious monitoring you want multiple regions and a "consider down only if 2+ regions fail" rule. Paid tiers offer it; free rarely does.

3. Alerts only by email (and email is slow)

The site went down at 3:47 AM. The alert went to your email. You only saw it at 8:30 AM. Four and a half hours of downtime with the customer cursing on WhatsApp.

For an alert to work, it has to be active: SMS, phone call, Telegram push, a webhook that calls PagerDuty. Almost all tools reserve this for paid tiers.

4. It doesn't check what matters, only whether it "responds"

Free checks: did the server return 200 OK? Yes → up. No → down.

It doesn't check:

• Whether the page has the expected keyword (detects "200 OK returning a generic error page")
• Whether the SSL certificate is close to expiring
• Whether the response time is degraded (slow but up)
• Whether the internal endpoints (checkout, login, API) are responding, not just the home
• Whether there's mixed content (HTTPS calling HTTP) breaking the site

For a serious business, "responded 200" is not "working".

5. Zero security audit

This is where almost all "pure uptime" monitoring falls short. Your site can be 100% up and still:

• Have an SSL certificate expiring in 3 days and nobody knows
• Have HTTP security headers missing (HSTS, CSP, X-Frame-Options)
• Have an outdated WordPress with a known CVE
• Have admin ports exposed (3306, 6379, 27017 open to the internet)
• Have an orphaned subdomain pointing to an abandoned Heroku/S3 (subject to takeover)
• Have email without SPF/DKIM/DMARC going to spam
• Have obfuscated JavaScript injected by an old breach
• Have an information leak in .env, .git, /backup.zip accessible at the root

100% uptime. And still at risk. Traditional "monitoring" tools look at none of this. That's what security auditing is for — and tools like Qualys, Detectify or Sucuri charge from USD 200/month.

What Sentinela does differently

We combined the two:

Uptime monitoring with:

• A check every 1 minute (HTTP, keyword, ping, port)
• Alerts by email, webhook and Telegram
• Public status pages with a custom domain
• Maintenance windows that silence alerts
• Full incident history

Automatic weekly/monthly security audit with more than 20 probes:

• TLS, headers, DNS, email (SPF/DKIM/DMARC), exposure, cookies, LGPD, ports, reputation, subdomains
• WordPress with CVE matching via Wordfence Intelligence
• JS bundle analysis (mixed content, SRI, libraries with a vulnerable version)
• Subdomain takeover detection
• Malware scan with URLhaus + OpenPhish
• A-F score + PDF report for the client or board

And the weekly email report consolidates uptime + security into a single document you send to the client or the CEO.

The free tier lasts a full 14 days — no card, no sticky trial. Create an account and in 2 minutes you have your first complete audit and the monitor already running.

Direct comparison

When traditional free is enough

There are scenarios where it's enough:

• Personal site, blog, portfolio
• You only want to know if it went down, not exactly when
• You can't pay anything
• You're learning about the topic

For those cases, UptimeRobot free is a solid choice.

When it's not enough

• Anything that generates revenue (e-commerce, SaaS, agency)
• You provide maintenance service to a client and need to show value
• You have WordPress (the #1 target of automated breaches)
• You want to sleep soundly knowing something warns you before the customer

That's where monitoring + auditing together makes the difference between finding the problem before or after the customer — and that difference, for any business, is worth far more than the price of a plan.

Start free today and see what the monitor + full audit finds on your own site in the first 5 minutes. There's almost always a surprise.