﻿---
title: Math processor
description: The Math processor evaluates arithmetic or logical expressions and stores the result in the target field. To calculate a value using an expression and...
url: https://docs-v3-preview.elastic.dev/elastic/docs-content/pull/4787/solutions/observability/streams/management/extract/math
applies_to:
  - Elastic Cloud Serverless: Generally available
  - Elastic Stack: Planned
---

# Math processor
The **Math** processor evaluates arithmetic or logical expressions and stores the result in the target field.
To calculate a value using an expression and store the result in a target field:
1. Select **Create** → **Create processor**.
2. Select **Math** from the **Processor** menu.
3. Set the **Target field** where you want to write the expression result.
4. Set your expression in the **Expression** field. You can directly reference fields in your expression (for example, `bytes / duration`).