Is GoRetro free?

GoRetro is not free but offers a 30 day trial with limited features.
Paid plans start at $29 USD/month per team (billed annually) for the Premium tier.
To access additional features like sprint capacity and poker planning, this would be the Sprint Pro Tier at $49USD /month for Sprint Pro tier.

TeamRetro also offers a 30-day free trial with full access to all features. After that, pricing starts at $20/month (billed annually) for the Single Team Plan, which supports up to 25 users. Plans scale by team, offering a Small Org Plan at $50/month for 3 teams, and a Large Org Plan at $75/month for 6 teams, all with unlimited users.