<!--
{
  "availability" : [
    "iOS: 26.0.0 -",
    "iPadOS: 26.0.0 -",
    "macCatalyst: 26.0.0 -",
    "macOS: 26.0.0 -",
    "tvOS: 26.0.0 -",
    "visionOS: 26.0.0 -",
    "watchOS: 26.0.0 -"
  ],
  "documentType" : "symbol",
  "framework" : "Swift",
  "identifier" : "/documentation/Swift/String/UTF8View/span",
  "metadataVersion" : "0.1.0",
  "role" : "Instance Property",
  "symbol" : {
    "kind" : "Instance Property",
    "modules" : [
      "Swift"
    ],
    "preciseIdentifier" : "s:SS8UTF8ViewV4spans4SpanVys5UInt8VGvp"
  },
  "title" : "span"
}
-->

# span

A span over the UTF-8 code units that make up this string.

```
var span: Span<UTF8.CodeUnit> { get }
```

## Return Value

A `Span` over the UTF-8 code units of this `String`.

## Discussion> Note: On Apple platforms, this property transcodes the code units
> of bridged UTF-16 `String` instances on first access and caches
> the result. Subsequent calls can reuse the cached buffer.

> Complexity: O(1) for native UTF-8 strings, amortized O(1) for bridged
> UTF-16 strings.

---

Copyright &copy; 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)