---
type: "fhirpath-operator"
title: "FHIRPath Operator: mod (mod)"
operator: "mod"
category: "Math"
section: "6.6.6"
source: "fhirpath/operations.json"
---
# FHIRPath Operator: mod (mod)
Computes the remainder of the truncated division of its arguments (supported for Integer and Decimal).

``` fhirpath
5 mod 2 // 1
5.5 mod 0.7 // 0.6
5 mod 0 // empty ({ })
```
## Summary
- **Category**: Math
- **Section**: `6.6.6`
- **Left Argument**: `Integer | Decimal`
- **Right Argument**: `Integer | Decimal`
- **Return Type**: `Integer | Decimal`
- **Empty Input Result**: `empty`
- **Errors on Multiple Input**: `true`
## Description
Computes the remainder of the truncated division of its arguments. Supported for Integer and Decimal. Each operand must be a single element. Modulo by zero results in empty collection.
## Type Mapping
- `Integer-Integer`
- `Decimal-Decimal`
- `Integer-Decimal`
- `Decimal-Integer`