CPM stands for 'cost per mille': Latin for 'per thousand.' A $5 CPM means $5 to serve one thousand impressions. The metric exists because impressions in advertising sell in batches, and CPM normalizes pricing across very different campaign sizes.
CPM by channel varies enormously. Programmatic display: $1-5. Native programmatic: $3-8. Connected TV (CTV): $25-60. Linear TV broadcast (primetime): $20-50. Out-of-home billboards: $5-10. Bar TV (Atmosphere, large networks): $15-30. Curated bar TV (Highfloor and similar): $25-60 depending on the metro and venue mix. Rideshare in-vehicle: $10-25.
CPM is a directionally useful but incomplete metric. Two campaigns at the same CPM can produce dramatically different attributed lift if the audience attention quality differs, and bar TV's defining advantage is attention quality, which means CPM-on-CPM comparisons against programmatic display systematically undersell the channel's value. Highfloor reports against attributed-lift metrics (visits, calls, ticket velocity) alongside CPM so the comparison is apples-to-apples.