Going from Kurdish to German (Deutsch) has a composite linguistic distance of 67% (heuristic estimate). Below is the dimension-by-dimension breakdown.
Shared vocabulary, cognates, and loanwords.
Morphology, syntax, word order, cases.
Shared sounds and phoneme inventory.
Latin/Arabic → Latin
Indo-European ↔ Indo-European
The 5 languages with the lowest linguistic distance from Kurdish:
A quick 3-question check between Kurdish and German. No signup.