---
type: "fhirpath-function"
title: "FHIRPath Function: round"
function: "round"
category: "Math"
section: "5.8.8"
source: "fhirpath/functions.json"
---
# FHIRPath Function: round
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> [Discussion on this topic](https://chat.fhir.org/#narrow/stream/179266-fhirpath/topic/round.28.29.20for.20negative.20numbers) If you have specific proposals or feedback please log a change request.
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Rounds the input to the nearest whole number using a traditional round (i.e. to the nearest whole number), meaning that a decimal value greater than or equal to 0.5 and less than 1.0 will round to 1, and a decimal value less than or equal to -0.5 and greater than -1.0 will round to -1. If specified, the precision argument determines the decimal place at which the rounding will occur. If not specified, the rounding will default to 0 decimal places.
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If specified, the number of digits of precision must be >= 0 or the evaluation will end and signal an error to the calling environment.
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Accepts input types of Decimal, or Quantity.
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When used with a Decimal input type, the result is an Decimal.<br/>
When used with a Quantity, the result is a Quantity with the same units.
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When used with Integer or Long, the arguments will be implicitly converted to Decimal before evaluation.
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If the input collection is empty, the result is empty.
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If the input collection contains multiple items, the evaluation of the expression will end and signal an error to the calling environment.
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``` fhirpath
1.round() // 1
3.14159.round(3) // 3.142
```
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## Summary
- **Category**: Math
- **Section**: `5.8.8`
- **Return Type**: `Decimal | Quantity`
- **Empty Input Result**: `empty`
- **Errors on Multiple Input**: `true`
## Description
Rounds the input to the nearest whole number using a traditional round (i.e. to the nearest whole number), meaning that a decimal value greater than or equal to 0.5 and less than 1.0 will round to 1, and a decimal value less than or equal to -0.5 and greater than -1.0 will round to -1. If specified, the precision argument determines the decimal place at which the rounding will occur. If not specified, the rounding will default to 0 decimal places.
## Arguments
- `precision` (optional): `Integer` - Optional decimal places to round to
## Type Mapping
- `Integer-Decimal`
- `Long-Decimal`
- `Decimal-Decimal`
- `Quantity-Quantity`
## Example
```fhirpath
1.round() // 1
3.14159.round(3) // 3.142
```