Neither Google Tag Manager nor Redpen offers a free trial.
Google Tag Manager is designed for Large Enterprises, Medium Business and Small Business.
Redpen is designed for Large Enterprises, Small Business and Medium Business.
The starting price of Redpen begins at $7.95per month when Billed Yearly, while pricing details for Google Tag Manager are unavailable.
Some top alternatives to Google Tag Manager includes Viraltag, Launch by Adobe, TagCommander, Tag Governance, Tealium iQ, Google Analytics, GingerTag, TapAnalytics, Tagmate and Scale8.
Some top alternatives to Redpen includes and undefined.