# `GSFont contextKerning(forKey:fontMasterID:)`

*Instance Method*

Contextual kerning value for a context key and master.

## Declaration

```swift
func contextKerning(forKey key: String, fontMasterID: String) -> CGFloat?
```

## See Also

### Contextual Kerning

- [`GSFont.kerningContext`](/Core/GlyphsCore/GSFont/kerningContext) — Contextual kerning data.
- [`GSFont setContextKerningForKey:fontMasterID:value:`](/Core/GlyphsCore/GSFont/setContextKerningForKey:fontMasterID:value:) — Sets the contextual kerning value for a context key and master.
- [`GSFont removeContextKerningForKey:fontMasterID:`](/Core/GlyphsCore/GSFont/removeContextKerningForKey:fontMasterID:) — Removes the contextual kerning value for a context key and master.
- [`GSFont replaceContextKerningKey:key:`](/Core/GlyphsCore/GSFont/replaceContextKerningKey:key:) — Replaces a context key while keeping its master values.
- [`GSFont parseContextKey:`](/Core/GlyphsCore/GSFont/parseContextKey:) — Parses a contextual kerning key into glyph tokens and class tokens.