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# maximumSignificantDigits

The maximum number of significant digits for the number formatter.

```
var maximumSignificantDigits: Int { get set }
```

## Discussion

You must set the [`usesSignificantDigits`](/documentation/Foundation/NumberFormatter/usesSignificantDigits) property to <doc://com.apple.documentation/documentation/Swift/true> in order for this property to affect formatting behavior.  By default, the maximum number of significant digits is 6. Values less than 1 are ignored.

The following code demonstrates the effect of setting [`maximumSignificantDigits`](/documentation/Foundation/NumberFormatter/maximumSignificantDigits) when formatting various numbers:

```swift
var numberFormatter = NumberFormatter()
numberFormatter.usesSignificantDigits = true
numberFormatter.maximumSignificantDigits = 4

numberFormatter.string(from: 12345) // 12340
numberFormatter.string(from: 123.456) // 123.5
numberFormatter.string(from: 100.234) // 100.2
numberFormatter.string(from: 1.230) // 1.23
numberFormatter.string(from: 0.00012345) // 0.0001234
```

---

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