To respond to some of the sibling comments:
1Password originally operated on a licensing model, but has since switched to a membership model.
It is still possible to purchase a single license, but they make it very difficult to do so. The option of a standalone license is not mentioned anywhere on their pricing page: https://1password.com/sign-up/
As I understand it, only once you have downloaded the app and are logging in do they mention that standalone licenses are available. (But, at least on Mac, this option is only available on the version of the app downloaded directly from their site, and not the version downloaded from the Mac App Store.) This support thread shows some users' frustration with this, and their support team's insistence on pushing users to the subscription model: https://1password.community/discussion/102412/where-do-i-buy...
I'm not entirely certain of the differences between the subscription model and the standalone version, but I believe the primary difference is that the subscription model will automatically sync your passwords between multiple devices.
You can achieve similar functionality with the standalone license version by storing your vault (1Password's password file) in iCloud or Dropbox, and relying on that for syncing. I use the Dropbox version and it works incredibly well, even on iOS! I think they also support Google Drive for syncing on desktop, but not on mobile. Certainly the syncing offered through their subscription model is valuable, but for users who have other options, it's just doesn't make sense.
I gladly paid for a standalone license, and have purchased licenses for my parents as gifts; the product is incredible. The Chrome extension works great, and the app can be your 2FA device, so it will automatically fill in password forms and copy the 2FA code to your clipboard. It works just as well on iOS too.