---
title: "Hysteresis band explained — Lemwatch Help"
description: "Lemwatch requires response time to fully clear a threshold before recovering, preventing oscillation alerts."
canonical: "https://lemwatch.com/help/hysteresis-band-explained"
source: "https://lemwatch.com"
---

# Hysteresis band explained

> Lemwatch requires response time to fully clear a threshold before recovering, preventing oscillation alerts.

## Quick answer

 If your alert threshold is 2000ms, Lemwatch won't mark the site "recovered" until response time drops below 1600ms (2000 − 20% band). This stops jittery pages toggling between degraded and healthy.

## What it does

- Adds a 20% clearance band below every threshold

- Requires the metric to fully cross the band before flipping status

- Applies to response time, TTFB, LCP, INP, and health score

- Prevents "recovered → degraded → recovered" alert loops

## Where to find it in Lemwatch

 **Site → Settings → Alert accuracy → Hysteresis band**.

## How to tune it

- Open the site's Alert accuracy settings.

- Adjust the Band width (default 20%) — wider = more stability.

- For very stable sites, drop to 10%.

- For noisy sites near threshold, raise to 30%.

- Save.

## FAQ

### Does this delay recovery alerts?

 Only when the metric hovers right at the threshold. Clear recoveries fire immediately.

### Does it apply to uptime status?

 No — uptime is binary. Hysteresis is for continuous metrics.

## Related

- Response time thresholds

- Flapping detection

- Why am I getting false alerts?


## Related

- [Help centre](https://lemwatch.com/help)
- [Response Time Threshold Alerts](https://lemwatch.com/help/response-time-thresholds)
- [Flapping detection](https://lemwatch.com/help/flapping-detection)
- [Why am I getting false alerts?](https://lemwatch.com/help/why-am-i-getting-false-alerts)
- [Reading the alert quality scorecard](https://lemwatch.com/help/alert-quality-scorecard)
- [Whitelist Lemwatch monitoring IPs](https://lemwatch.com/help/lemwatch-ip-whitelisting)
- [Lemwatch pricing](https://lemwatch.com/pricing)
- [Ignore zones for visual monitoring](https://lemwatch.com/help/ignore-zones)