HetrixTools is a monitoring service with a generous free tier, popular with hosting providers, sysadmins and agencies. If you are searching for an alternative, you probably want to compare scope or simply have a second option. This page compares it with SiteDownCheck, a new and small service, and tries to be straight about what we cannot match.
What we say about HetrixTools comes from its homepage as read in October 2026. Plans change, so check their pricing page before deciding. Our own facts come from our pricing page.
What HetrixTools says it offers
According to its homepage, HetrixTools has two core products. The uptime monitor checks websites and servers every minute from 12 global locations, with alerts through more than 20 channels, and a free tier of 15 monitors that is described as indefinite. The blacklist monitor tracks IP addresses and domains against major blacklists, with a free tier of 32 monitors. It also describes free server monitoring agents for Linux, Windows and macOS, unlimited public status pages, outage snapshots with error logs and MTR data, and an MCP server for querying monitoring data through an API.
We could not confirm from the pages we read which check interval applies to the free uptime plan specifically, so verify that on their pricing page. The one-minute figure on the homepage describes the product, not necessarily the free tier.
Side-by-side
| HetrixTools | SiteDownCheck | |
|---|---|---|
| Free uptime monitors | 15 per their homepage | 3 |
| Free check interval | Check their pricing page | 5 minutes |
| Check locations | 12 global locations per their homepage | One default location on the free plan |
| Blacklist monitoring | Yes, 32 free monitors per their homepage | One-off blacklist checker; no continuous blacklist monitor |
| Server monitoring agents | Yes, free agents per their homepage | Not offered |
| Status pages | Unlimited public pages per their homepage | 1 public status page on the free plan |
| Alert channels | 20+ per their homepage | Email, Slack, Discord, any HTTPS webhook |
| SSL and domain expiry alerts | Check their docs | Included on every monitor |
| Keyword and JSON checks | Check their docs | Included |
| Heartbeat (cron) monitors | Described as agent-based in docs | Included, counts toward your 3 |
| Free API | Check their docs | 200 requests per day |
| Maturity | Established | New and small |
Where HetrixTools is stronger
- Free capacity. Fifteen uptime monitors and 32 blacklist monitors dwarf our three.
- Locations. Twelve probe locations let you tell a regional issue from a global one. We run from a single default location on the free plan, so we cannot.
- Blacklist monitoring. If you run mail servers or shared hosting and care when an IP lands on a DNSBL, continuous monitoring is exactly what you want. We offer a free one-time blacklist checker, not ongoing monitoring.
- Server health. CPU, RAM, disk and RAID monitoring through an agent covers the inside of the server. We only check from the outside.
- Diagnostics on outage. Snapshots with error logs and MTR data on an outage are useful for hosting providers. We provide a failing-layer explanation (DNS, TCP, TLS, HTTP or content) through our root-cause finder, but no traceroute snapshots.
Where SiteDownCheck fits better
- A simpler path for site owners. If you run a business site rather than a fleet of servers, a short setup with URL and email may be all you need.
- Content and API checks on the free plan. Require a keyword on the page or a value in a JSON response, such as
statusordata.db.ok, to catch a 200 that is really an error. - Clear failure rules. One failed check does not alert; we re-check, and 5xx, 404 and 410 count as down while 401, 403 and 429 count as up with restricted access.
- A tidy bundle of expiry warnings. SSL, domain, DNS record and certificate change alerts attach to the monitors you already have.
- Badges and a monthly report. SVG uptime badges for a README and an emailed monthly report are included.
- A single friendly toolbox. The free DNS, SSL and HTTP checkers sit under the same roof, with no account needed.
Who should choose what
Choose HetrixTools if you run servers, host client sites, manage mail infrastructure, need blacklist monitoring, or want more free monitors and several probe locations.
Choose SiteDownCheck if you have a few websites or endpoints and want straightforward alerts, expiry warnings and a status page, with no agents and nothing to install.
Choose both if you are a sysadmin: HetrixTools for fleet-level monitoring and blacklists, and a second, independent monitor on the three URLs that matter most. Two networks checking the same site is a cheap way to stop chasing false alarms, which our false-alert guide covers in detail.
About our limits
We are new. We do not offer server agents, continuous blacklist monitoring, scripted browser checks or SMS today. Pro is planned to add 50 monitors, 1-minute checks, SMS and phone alerts, custom-domain status pages and multi-region checks. There is no price or launch date yet, and the free plan stays when it launches.
Next steps
- Create a free monitor on a site you care about.
- Run a one-off blacklist check on your mail server IP.
- Read email blacklist removal if you are listed.
- Use down from where to see how a site responds from our probe.
- Set up a status page.
FAQ
Does SiteDownCheck monitor blacklists continuously?
No. We offer a free one-time blacklist checker. For continuous blacklist monitoring, use a service that sells it.
How many locations does SiteDownCheck check from?
One default location on the free plan. Multi-region checks are planned for Pro, with no date.
Can I monitor servers with agents?
Not with us. We check from the outside: HTTP, content, SSL, DNS and heartbeat pings.
Is the free plan limited in time?
No. There is no trial period and no credit card. It is limited by size: 3 monitors checked every 5 minutes or slower.
Try SiteDownCheck free
3 monitors, 5-minute checks, email and webhook alerts and a public status page. No credit card.
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