User guide
ZeroDrop is a free uptime monitor with multiple locations. It probes your HTTP endpoints and mail servers from several points around the world. A consensus of those locations decides whether a service is down. ZeroDrop tells you when an incident opens or closes.
This guide covers what you can do from the console. It explains how to create checks and how to tune when they alert. It also covers notification channels, maintenance windows, and the security of your account.
How it works
ZeroDrop has three parts. You do not run any of them yourself.
- Locations are independent probing agents in San Francisco (SFO), New York (NYC), Amsterdam (AMS) and Sydney (SYD). Every check runs from all active locations. As a result, one unreliable network cannot cause a false alarm.
- The collector gathers the results from each location on every interval. It then asks the evaluator for a verdict.
- Consensus declares a check down only when enough locations agree, for enough consecutive evaluations. This keeps ZeroDrop quiet until a service is really down. See Consensus & status.
A check has three states: ok, firing (down), and unknown. The unknown state means that ZeroDrop cannot see enough locations to make a verdict. A change into or out of firing opens or closes an incident. Incidents trigger your notifications.
What you can monitor
| Type | What it does | Page |
|---|---|---|
| HTTP / HTTPS | Requests a URL. Examines the status code, the body and the TLS certificate, and records the timing. | Checks |
| SMTP | Connects to a mail server and measures the time to the welcome banner, with STARTTLS if you want it. | Checks |
Start here
- Getting started: create your account and your first check.
- Checks: every setting on an HTTP or SMTP check.
- Consensus & status: how ZeroDrop decides up or down.
- Incidents & alerts: notification channels and what ZeroDrop sends.
- Maintenance windows: silence expected downtime.
- Dashboards: the overview, the check detail page, badges and the global board.
- Account & security: passwords, two-factor, passkeys, API tokens.
- API examples: sync checks and render a private dashboard, in Python.
- Settings: account name, timezone, notifications, theme and limits.
ZeroDrop is free. No subscription is necessary. Every account gets monitoring from all locations at a one-minute interval by default.