Kahl, who was born in San Francisco, California, is often considered the finest draughtsman of the Disney animators. He would often refine the characterssketches from Bill Peet with the ideas of Ken Anderson. For many years the final look for the characters in the Disney films were designed by Kahl, in his angular style inspired by Ronald Searle and Picasso. He is revered by contemporary masters of the form, such as Andreas Deja, and Brad Bird, who was his protégé at Disney in the early 1970s. In the behind-the-scenes feature "Fine Food and Film" shown on the Ratatouille DVD, Bird referred to Kahl as "tough", but in a gentle way, as he often gave Bird advice on where he could improve in animation whenever he came up short.
In the book The Animator's Survival Kit, the author Richard Williams makes repeated reference and anecdotes relating to Kahl. The centenary of Kahl's birth was honoured by the Academy on April 27, 2009, with a tribute entitled "Milt Kahl: The Animation Michelangelo" and featured Brad Bird as a panelist.