So, concretely: $0.40/secret/month (prorated if < 1m) + $0.05 per 10,000 API calls. KMS: $1/CMK/mo + $0.03 per 10,000 requests.
What are you doing with it that makes it a major expenditure? That seems like a drop in the bucket compared to anyone's compute. Are you dumping 500 secrets in it?
We were looking at it for a configuration management backend. So, yes, 500+ values, consumed by microservices.
I still say - the only real value even when compared to other AWS services is the rotation, which currently only really works with DBs (and then only if your service connects to the Secrets Manager directly, with every DB open).
Just a note on Secrets Manager which you probably know, but is worth mentioning just in case:
Secrets Manager charges per Secret, but if you are storing non AWS values (API keys), then you can put several secret values in one Secret. Not sure if your 500 values number was 500 Secrets, or 500 secret values which could perhaps be grouped logically together into a smaller number?
Yep, definitely not debating that it's overpriced and questionable value compared to KMS + storage of your choosing -- just surprised that you ended up with a model where it's nontrivial cost :)
What are you doing with it that makes it a major expenditure? That seems like a drop in the bucket compared to anyone's compute. Are you dumping 500 secrets in it?