Yes! env0 is really free during our public beta. Once the beta is over, existing users will be given a special upgrade offer.
An "active environment" is any environment managed through env0 that is currently running. Environments that have expired or been manually disabled don't count towards your active environments.
Our pricing is based on the total number of active environments you need to support at a time - if you need more, we'll just add an additional "pack" to your next bill.
NOTE: Additional environments are also free during the beta