Marni is a distinctive girls' name in England & Wales, ranking #929 in 2004 with 28 recorded births. This places Marni in the top 15% of ranked UK girls' names for the year. Its actual usage is classified as Uncommon. The name reached its all-time peak in 2014 with 48 births ranking #802. Since 1996, the popularity has increased by 366.7%. In 2004, approximately 1 in every 10,209 girls born was named Marni. FALLING Recent data shows the name is currently falling.