---
title: "Flapping detection — Lemwatch Help"
description: "How Lemwatch suppresses monitors that flip up/down repeatedly instead of paging you every flip."
canonical: "https://lemwatch.com/help/flapping-detection"
source: "https://lemwatch.com"
---

# Flapping detection

> How Lemwatch suppresses monitors that flip up/down repeatedly instead of paging you every flip.

## Quick answer

 A monitor is "flapping" when its status flips 3+ times in 15 minutes. Lemwatch sends one summary alert instead of paging you per flip.

## What it does

- Tracks status transitions in a 15-minute rolling window

- Marks the monitor flapping at 3+ transitions

- Sends one "flapping detected" alert, then goes quiet

- Sends a "flapping resolved" alert once stable for 15 minutes

## Where to find it in Lemwatch

 **Site → Settings → Alert accuracy → Flap detection**.

## How to tune it

- Open Alert accuracy for the site.

- Adjust Transitions to flap (default 3) — lower = more aggressive.

- Adjust Rolling window (default 15 min) — shorter = catches faster flaps.

- Optionally route flap alerts to a lower-priority channel.

- Save.

## FAQ

### Do I still get the underlying down alert?

 Yes — the first down alert always fires. Flapping suppression starts on the third transition.

### Does flapping affect uptime %?

 No. Every transition is recorded in history; only alerting is suppressed.

## Related

- Why am I getting false alerts?

- Alert confirmation gates

- Hysteresis band


## Related

- [Help centre](https://lemwatch.com/help)
- [Why am I getting false alerts?](https://lemwatch.com/help/why-am-i-getting-false-alerts)
- [Alert confirmation gates](https://lemwatch.com/help/alert-confirmation-gates)
- [Hysteresis band explained](https://lemwatch.com/help/hysteresis-band-explained)
- [Rotating content noise (visual + text diff)](https://lemwatch.com/help/rotating-content-noise)
- [Lemwatch pricing](https://lemwatch.com/pricing)
- [Fleet Health Overview](https://lemwatch.com/help/fleet-health)
- [Fixing 5xx errors caused by your firewall](https://lemwatch.com/help/fixing-5xx-errors-from-firewall)