now

Use the now function in APL to return the current UTC clock time as a datetime value, optionally offset by a given timespan. now is evaluated once at the start of the query and returns the same fixed value for the entire duration of the query, regardless of how long the query takes to run. This means all uses of now within a query refer to the same point in time.

You can use now to calculate relative times, filter events by recency, and compute the age of records in your dataset.

Use it when you want to:

• Filter events to a recent time window.
• Calculate how long ago an event occurred.
• Add the current timestamp to query output for audit or comparison purposes.

Usage

Syntax

now([offset])

Parameters

Returns

The current UTC clock time as a datetime. All references to now() within a single statement return the same value.

Use case examples

['sample-http-logs']
| extend age_hours = datetime_diff('hour', now(), _time)
| project _time, age_hours, method, status
| take 10

['otel-demo-traces']
| where _time > now(-5m)
| summarize trace_count = count() by ['service.name']

['sample-http-logs']
| where toint(status) >= 400
| extend current_time = now()
| extend time_since = datetime_diff('minute', current_time, _time)
| project _time, current_time, time_since, status, uri
| take 10

List of related functions

• ago: Subtracts a given timespan from the current UTC clock time.
• datetime_add: Adds a specified amount to a datetime value.
• datetime_diff: Calculates the difference between two datetime values.
• startofday: Returns the start of the day for a datetime value.
• endofday: Returns the end of the day for a datetime value.

Other query languages