Calculates the rate for a counter field. This function can show the rate at which a counter changes. The result is returned in a field named _rate with the unit being events/second.

counterAsRate() is often expected to be used as the function parameter in a timeChart() or groupBy() function.


This function requires at least two points for calculating a rate. When used in a Time Chart, it is important to have at least two points in each bucket.

This function expects the field to have monotonic increasing values over time. If this is not the case no result is returned. Counters are often reset at server restarts or deployments. Running rate over a reset would not return a result. Using counterAsRate() in a timeChart() returns a rate for each bucket where the counter was not reset and nothing for the buckets where the counter was reset.

asstringoptional[a]_rate Name of output field.
field[b]stringrequired  Field from which to extract a number and over which to calculate rate.

[a] Optional parameters use their default value unless explicitly set

[b] The argument name field can be omitted.

Omitted Argument Names

The argument name for field can be omitted; the following forms of this function are equivalent:




These examples show basic structure only; full examples are provided below.

Show the rate of a counter over time:


Show the rate of a counter with one series for each host over time, displaying the rate as events per minute:

timechart(host, function=counterasrate(counter), unit="1/sec to 1/min")