Healthchecks.io alternative: heartbeats plus active checks in one place

What Healthchecks.io does well

Healthchecks.io is a passive monitor, sometimes called a dead man switch. Your job pings a URL when it finishes. If the ping does not arrive on schedule, you get alerted. That is the whole product, and it is executed about as well as a single-purpose tool can be.

• It is open source under a BSD 3-clause license and genuinely self-hostable, which is rare for a hosted SaaS and worth respecting.
• The free Hobbyist tier covers up to 20 monitored jobs, which is more than most people need for cron monitoring alone.
• The ping URL is a plain HTTP endpoint that works over HTTP/1.0, HTTP/1.1, HTTP/2, IPv4 and IPv6, with GET, HEAD, or POST. Anything on any machine can hit it.
• It has richer job semantics than a bare heartbeat: a /start suffix to record run duration, a /fail suffix to report a failure explicitly, a /log suffix for context, and exit-status reporting so a non-zero exit is an alert rather than a silent success.
• Configurable grace time lets you say how late a ping may be before it counts as a miss, which matters a lot for jobs with variable runtimes.
• Public status badges on hard-to-guess URLs, handy for dropping into a README or an internal dashboard.
• It offers a free Business plan to verified open source projects and nonprofits, which is a genuinely decent thing to do.

If your problem is precisely "did my backup script run last night", Healthchecks.io solves it cleanly and you should feel no urgency to move.

The gap: it never checks your site

Healthchecks.io does not make outbound probes. It will never fetch your homepage, never open a TCP port, never resolve a DNS record, never validate a certificate chain. It waits for you to call it. That is a deliberate design choice and it makes the product simple, but it means it can only ever cover half of what most teams need.

The result is a familiar setup: Healthchecks.io for cron jobs, some other service for uptime, a third thing for the status page, three dashboards, three alert configurations, three bills, and three places to check when your phone buzzes at night. Undownable exists partly to collapse that.

Side by side

Where Undownable differs

The short version: Undownable does heartbeats and active checks and status pages, in one account, on one alert configuration.

• Push heartbeats at a private ping URL, same idea as Healthchecks.io, for cron jobs, backups, queue workers, and self-hosted monitoring boxes.
• Active checks in the same account: HTTP and HTTPS, keyword matching, JSON API assertions with dot notation, TCP ports, ping, DNS records, and SSL certificates.
• SSL checks verify the full chain and the hostname, not just the expiry date, with escalating warnings at 30, 14, 7, and 1 days out.
• Public status pages that show your heartbeat monitors and your uptime monitors together, on your own domain on Pro.
• One alert setup for all of it. Configure Slack once and it covers the backup script and the checkout page alike.
• Every alert channel on every plan, free included, with no metered SMS credits to run out at the wrong moment.
• Exactly-once delivery, flap suppression, confirmation thresholds, a degraded state distinct from down, and maintenance windows.
• A versioned REST API and an MCP server with least-privilege, team-pinnable tokens.

Who should stick with Healthchecks.io

• You only need cron monitoring, and you need a lot of it. Healthchecks.io scales job counts more cheaply than a general monitoring plan will.
• You want to self-host. Undownable is a hosted service; Healthchecks.io ships you the source under a permissive license.
• You depend on the richer job semantics: start pings for duration tracking, explicit failure pings, exit-status reporting, and per-run log capture.
• You need SMS or phone-call escalation for job failures and are happy buying credits for it.
• You are an open source project or nonprofit eligible for their free Business plan.

A perfectly reasonable hybrid exists too: keep Healthchecks.io for deep cron instrumentation, and add a handful of free Undownable checks for the public surfaces and the certificate. Nobody is going to talk you out of a setup that works.