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<!--
title: "Median"
description: "Use median in API queries and health entities to find the 'middle' value from a sample, eliminating any unwanted spikes in the returned metrics."
custom_edit_url: https://github.com/netdata/netdata/edit/master/web/api/queries/median/README.md
-->
# Median
The median is the value separating the higher half from the lower half of a data sample
(a population or a probability distribution). For a data set, it may be thought of as the
"middle" value.
`median` is not an accurate average. However, it eliminates all spikes, by sorting
all the values in a period, and selecting the value in the middle of the sorted array.
## how to use
Use it in alarms like this:
```
alarm: my_alarm
on: my_chart
lookup: median -1m unaligned of my_dimension
warn: $this > 1000
```
`median` does not change the units. For example, if the chart units is `requests/sec`, the result
will be again expressed in the same units.
It can also be used in APIs and badges as `&group=median` in the URL.
## Examples
Examining last 1 minute `successful` web server responses:
- 
- 
- 
- 
## References
- <https://en.wikipedia.org/wiki/Median>.
[](<>)
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