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Contextual Kerning Tool (Prototype)

The "Contextual Kerning Tool" is a proof of concept for a new tool to aid the kerning process.

  1. It reads your font's kerning and use it to inspect a dictionary and generate kerning words tailored tu your fonts kerning pairs.
  2. Shows a "Bird's eye" view of your kerning pairs, much more intuitive than the standart "list view" used by font editors.
  3. Allows you to easily compare kerned pairs between 2 fonts (may be completely different fonts or different version of the same font)

Spliting the Dictionary in two:

Use YOUR FONTS KERNING PAIRS to split the dictionary in two:

  • Spacing Words: Words that are solved by using only spacing and no kerning pairs at all
  • Heavily Kerned Words: Words that have 5 or more kerning pairs each

This list are customized for each font, and once you have those custom list of words its very easy to test spacing and kerning separately and spot kerning consistency problem. For example: A word having not kerning at all may show a certain rithm, while a heavily kerned word may show a corrupted rithm becouse of the sum of all the kerning pairs.

By looking at the list of words that are resolved using spacing only, if there is any problem whit the kerning, it will become self evident.

And by looking at the list of heavily kerned words you can spot inconsistency cases (where you have set some individual pair overly tight or overly loose). Since they are displayed one after another, minor differecnes add up, and any incosistency will quickly pop up.

Bird-eye view of your kerning pairs:

Reading your list of kerning pairs in the traditional list view is far from ideal.

This tools gives you an easy to scan "birds eye" view of your kerning pairs.

It also shows you the list of pairs that you have not kerned. It sounds silly, but its actually quite usefull to quickly detect pairs that should be kerned and for some reason you forgot. It also enables you to kern as you go, instead of kerning at the end of the design process.

Sample Images:

Lowercase Pairs and Word list: Lowercase Pairs.

Uppercase Pairs and Word list: Lowercase Pairs.

Capitalized Pairs and Word list: Lowercase Pairs.

Compare kerning in two fonts:

You can also easily compare the kerning in:

  • Two different fonts (Source Sans vs. Roboto), or..
  • Two different versions of the same font (LibreFranklin v1.000 vs. LibreFranklin v2.000), or..
  • Two different weights of the same family (Thin vs Heavy).

Comparing Fonts: Lowercase Pairs.

How to make it works:

Since this is only an initial prototype, operation is precarious and tedious and involves a lot of manual steps that hopefully will be automated. Ideally I will love to see this idea implemented as a Glyphs plugin by someone.

A mixture of python scripts, php files editing, and uploading files to a php server: By the way, I hate this method, but currently it is what is is...

  • First, upload all the files inside a new folder in your php hosting
  • Next, you need to make a copy of your font and manually expand the kerning table
  • Next, you need to run this Fontlab Macro to export the kerning pair list into .txt files
  • Next, you need to generate a .php pair list file for the font you want to use (similar to the ones inside the "pairs" folder) and copy the data from the txt files into the proper php variables
  • Next, you need to upload your new pairs php file into the pair folder
  • and finally, edit the "configure.php" file to include your php pair file
  • if you want to compare two fonts, also edit the "config-compare.php" file to include both pair files.


1st prototye






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