---
type: "fhirpath-function"
title: "FHIRPath Function: precision"
function: "precision"
category: "Utility functions"
section: "5.10.7"
source: "fhirpath/functions.json"
---
# FHIRPath Function: precision
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If the input collection contains a single item, this function will return the number of digits of precision.
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The function can only be used with Decimal, Date, DateTime, and Time values.
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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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For Decimal values, the function returns the number of digits of precision after the decimal place in the input value.
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``` fhirpath
1.58700.precision() // 5
```
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For Date and DateTime values, the function returns the number of digits of precision in the input value.
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``` fhirpath
@2014.precision() // 4
@2014-01-05T10:30:00.000.precision() // 17
@T10:30.precision() // 4
@T10:30:00.000.precision() // 9
```
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## Summary
- **Category**: Utility functions
- **Section**: `5.10.7`
- **Return Type**: `Integer`
- **Empty Input Result**: `empty`
- **Errors on Multiple Input**: `true`
## Description
If the input collection contains a single item, this function will return the number of digits of precision. The function can only be used with Decimal, Date, DateTime, and Time values.
## Arguments
- none
## Type Mapping
- `Decimal-Integer`
- `Date-Integer`
- `DateTime-Integer`
- `Time-Integer`
## Example
```fhirpath
1.58700.precision() // 5
@2014.precision() // 4
@2014-01-05T10:30:00.000.precision() // 17
@T10:30.precision() // 4
@T10:30:00.000.precision() // 9
```