---
title: Alert thresholds
description: Require a few failures in a row before we alert, to avoid noise.
category: configuration
updated: 2026-07-15
tags: [thresholds, confirmations, debounce]
---

The internet is noisy. A single failed check often means nothing — a momentary blip,
not a real outage. Alert thresholds let you require a few failures **in a row**
before a monitor is officially marked down, so you only hear about problems that
stick.

![The Alert Thresholds section of the Add Monitor dialog, with fields for consecutive failures before a monitor is marked down and consecutive successes before it is marked up, and a note describing it as Nagios-style debouncing](/img/docs/app-alert-thresholds.png)
*Both directions are configurable: how many failures before we call it down, and
how many successes before we call it recovered.*

## The two settings

Each monitor has two thresholds:

- **Failures before Down** — how many checks must fail in a row before the monitor
  is marked down and you're alerted. Default: **3**.
- **Successes before Up** — how many checks must pass in a row before it's marked
  back up and a recovery is sent. Default: **2**.

Both can be set from 1 to 20.

## How to tune them

- **Fewer failures (e.g. 1–2)** — you find out faster, but you'll get the occasional
  alert for a blip that recovers on its own.
- **More failures (e.g. 4–5)** — quieter and more certain, but you learn about a real
  outage a little later.

A good starting point is the default of 3 down / 2 up. If a particular monitor is
flappy, raise its "failures before Down". If it's rock-solid and you want the
earliest possible warning, lower it.

## What this doesn't affect

Thresholds only control **when we alert you**. The individual check results still
show up in the monitor's history, so your uptime graphs stay accurate either way.

## Get started

- [Set up notification channels](/docs/alerts/notification-channels)
- [Review how alerts work](/docs/alerts/how-alerts-work)

## Related

- [Check intervals](/docs/configuration/check-intervals)
- [Maintenance windows](/docs/alerts/maintenance-windows)